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Windows Home Directory Encryption?
An anonymous reader writes "Home directory encryption has been available on Linux for a while now, and it is definitely a smart, useful feature as it is not usually necessary to encrypt the entire drive, just the private documents and software profiles in the home directory. Windows is getting better about keeping everything that needs to be private in the user's home folder. Is there a similar solution for Windows to securely, and preferably transparently, encrypt the home directory only? (Preferably open source so that the code is available for peer review)."
But it usually comes with an email demanding money for decryption. If you want to keep something private, you should not use Windows.
make a truecrypt image, copy over the userprofile folder and make a junction to it.
Comment removed based on user account deletion
(1) Right Click the directory
(2) Left Click Properties
(3) Left Click "Advanced" near the bottom
(4) Check with you Left Moust button "Encrypt contents to secure data"
(5) Left Click OK, wait until it finishes
The directory would appear green thereafter, indicated it's encrypted and can only be accessed by the owner. Home edition might not have encryption enabled, mind you.
Google for "windows directory encryption" would lead you to the answer anyway.
"Preferably Open Source".
I know its possible to make user directories private from within windows, and I'd be surprised if microsoft didn't have an existing policy for rolling out EFS (as stated above) to user folders.
If this is a single computer not on a network, why not use truecrypt to encrypt the entire drive? I have not noticed ANY slow down on any relatively modern system running whole drive encryption. Its a simple 45 minute process for less than 100gig drives.
I'm not familiar with any open source alternative to this, but you shouldn't have to look anywhere beyond the tools available on a windows active directory.
Is it sad that I am more likely to recognize you and your posts by your sig than your name or UID?
Truecrypt can encrypt the entire OS partition.
"preferably"
Enterprise and government have access to the Windows source to review it. Unless you are suggesting that OP plans to read through it himself?
3laws: No freebies, no backsies, GTFO.
"Pref"
EFS.
/e /s on your profile dir. 5 seconds of googling surely would have revealed this.
Right click on your profile, go to properties, advanced, check the encrypt box. Alternatively, cipher
If you put it that way, there physically cannot be an open source solution here, because Windows itself is closed-source.
No matter how great open-source encryption software you can find,
On Windows, you can't have a home directory, let-alone run software to be able to encrypt it, without running closed source software.
The advantage of EFS (Encrypted Filesystem), is it doesn't require any additional software to implement, open source, or otherwise.
I use EFS for some folders at work... but at home I cheaped out and got Windows Home edition... or whatever Vista's non-Business edition is called. I use TrueCrypt for the really critical files.
and do those companies and/or governments choose to implement it?
Vista introduces something where you can encrypt C: using the TPM chip on your motherboard as a key...
I think on Windows one can have a home directory but I don't know whether you can make it a mount point for a separate partition encrypted transparently (which would ease maintenance). Anyway, I'm not sure... haven't used Windows for quite some time.
Colorless green Cthulhu waits dreaming furiously.
Yeah. It isn't open source, but the OP didn't seem to "require" it. Also, EFS isn't available on XP Home or Vista Home, but if he has the pricier editions then it's no problem.
I think there are two major/popular ways to do what you want that I'm familiar with. There are of course other options, but I've not used them, and won't comment on them.
1. TrueCrypt
This is a simple but very powerful encryption utility that is also open-source. It performs its magic by either encrypting volumes or by using encrypted file containers (a file which contains encrypted data that can be mounted as a virtual drive). The file container approach is very easy to use but you won't be able to use it to encrypt your _entire_ home directory, only elements of it. Effectively, you'd create one or more encrypted file containers and store everything sensitive in them. You could use full volume encryption by storing your entire user profile on a seperate volume, but this is obviously more difficult to setup, depending on your OS. To do something like the latter properly in something like Vista, you'd probably need to do it at install time through an unattend and state which drive the Users directory should be located on, as changing this once installed is not simple and ill-advised.
2. NTFS EFS (Encrypting File System)
Included with all "professional" (ie. not Home/Starter/etc..) editions of Windows since Windows 2000. Enables file-system level encryption tied into NTFS to encrypt individual files/folders on any NTFS device. This has some significant pros, in that not only is it included as a stock component of the OS, but is extremely easy to setup. Just right click on the folder/file you want to encrypt and do so through the Advanced properties. However, getting into the guts of EFS and fiddling with encryption certificates, ciphers, etc... requires some additional skill and research as there is no simple unified front-end to managing EFS like there is for TrueCrypt.
It's important to note that these two encryption suites are very different in how they work. Whereas TC stores data in file containers (unless you encrypt the entire volume), EFS works at the filesystem level and is completely transparent to userland, enabling transparent encryption of anything on the NTFS volume that is user-related. Note that EFS binds to user accounts. You generally can't use EFS to encrypt data that is outside the scope of a user account (such as system files). You'll need full volume encryption technology for that.Microsoft also has BitLocker for full-volume encryption, but this is Vista only, and for home setups, needlessly complicated and difficult to setup, not to mention the TPM requirements for full functionality.
Other things to note would be the importance of portability. TrueCrypt works across Windows/Unix, whereas EFS is obviously specific to Microsoft. I'm not sure if there's an OSS implementation for reading EFS encrypted data under Unixes, but even if there was, I think you'd be mad to use it. You shouldn't be using EFS if portability between OS's is a concern. Also note that whereas TC will have a seperate password, EFS will use your account password for encrypting your user data. This means that if you lose/forget your account password, you _WILL_ lose your EFS encrypted data, unless you've set up things like recovery certificates. Further, if you use a password reset tool to reset your account password outside of your user account, you _WILL_ lose all your EFS encrypted data. Your account password is the key to your EFS data, and so losing it or changing it improperly can have very nasty consequences.
I can't really recommend either method, you really need to research and have a play with both to decide which you prefer. I will say that if you are going the full-volume encryption route, I'd highly recommend TrueCrypt over BitLocker for home setups. The general trend I've observed from using both is that they both are very powerful tools, and can both easily get the job done when setup properly. However, TrueCrypt is more geared towards home/smaller setups, while EFS/BitLocker can work on anything from an individual box to a centrally managed enterprise network. T
In Windows they call home directories 'user profiles'. Commonly (in a windows domain environment), they live on a server, and automatically get copied to whatever workstation you log into.
Folders in there could be encrypted, however, certain folders in your profile are loaded by the system, and you may be unable to login if they get encrypted.
If you use EFS, your certificates and private keys for actually decrypting/encrypting files, are stored in your profile too.
Downside of EFS: your home directory decryption is linked to your login password, and a digital certificate.
If someone alters your password not through the normal password change process (i.e. an Administrator uses 'reset password'), you lose access to your private keys, and thus your encrypted files.
Because the cert and keys in the keystore are required, if you backup encrypted files to a USB thumbdrive using NTFS, you can't read them on another computer, even if you know the login password you were using when you encrypted them.
*It's too dumb to realize you only want it encrypted while it's in that folder.
and it doesn't integrate open source software. The closest thing to the "home" directory on Windows is Documents and Settings -> User Name.
I don't recommend encrypting your "home" directory on Windows, because Windows tends to self destruct, and the last thing you want is for your data to be lost permintaly when that happens. If you have specific files you need to encrypt, try AxCrypt, make sure you have a portable version of AxCrypt to decrypt the files if needed.
Author said he wanted only the home directory (I'm assuming you mean %USERPROFILE%) encrypted. While TrueCrypt can natively encrypt the entire drive, there is an addon available to perform only encryption on your "Documents and Settings\Username" folder. The enhancement is available at http://tcgina.t35.com/ Of course, truecrypt is available at www.truecrypt.org Even though I use truecrypt for the entire drive, I separately use TCGINA so that I can have a portable encrypted container of just my user profile, so that I have a compact way to transport my documents, program settings, etc.
"Pre"
If you're concerned enough to consider encrypting your home directory, you ought to go all the way and use full disk encryption. There are too many artifacts that can escape your home directory (RAM contents saved to swap file or hibernation file) or are never in your home directory to begin with (system logs, print spool, etc).
One very important thing to remember if you choose to use Windows built in encryption is that it uses the Windows password to encrypt the keys, and by default that password is stored using an LM hash which is extremely insecure (in addition to the NTLM which is less insecure).
To prevent this, you can either modify a registry setting to disable LM Hashes, or you can pick a password 15 characters or longer (since LM is limited to 14, it will be filled in with garbage and NTLM used instead).
Note that this also applies if you use TrueCrypt or some other program, but use the same password as you use for Windows.
Pie? I like pie!
Put your homedirectory on a separate partition (a very good idea anyways) and then encrypt that using truecrypt. You can also encrypt a less-tnan-professional simgle-partition installation, the overhead for encryption is not too bad.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
truecrypt is not an automated process (that I know of), it sorta works if you have portable apps and config files you can import/export, but you'd have to "mount" it, then prob log in. while I've never had need to use ntfs file encryption it would be first -- free option to try I'm sorta wondering what options will be replied so gonna watch this topic myself. oh wells Geo
mmmmm...
Hair Pie...
Some people are only alive because it's against the law for me to hunt them down and kill them.
I've found that CrossCrypt is a really good solution--entirely open source--that works on any version of NT.
If you do not have a separate partition, CrossCrypt will also allow you to mount a file as a drive. This comes in really handy for mounting ISO images as well.
The only tricky bit is if you want to set your entire user profile directory (including registry) to the mounted partition, because this means that you would need to have to run the encryption before you login--probably requiring an administrator user. In my opinion, not worth it. Doing this correctly would probably require magic with a GINA, Service, Utility Manager script, or HKEY_USERS\.Default\ControlPanel\Desktop\SCRNSAVE.EXE
But if you just want to encrypt individual folders, it is simple to do manually using this. And also much more manageable since you don't need the folder decrypted all the time while you are logged in--you just decrypt it to load a document, and unmount the partition once you are finished.
Better be careful with that. Full disk crypto doesn't work unless you're disciplined enough to properly shut Windows down at the end of the day, which means every time you boot you'll lose the usual 15 minutes before you have a usable system.
File based crypto can be set to disconnect on a more useful set of circumstances..
IMHO you need BOTH for good protection.
Insert
"If someone alters your password not through the normal password change process (i.e. an Administrator uses 'reset password'), you lose access to your private keys, and thus your encrypted files."
This is only true for local (eg, non-domain) accounts. Domain account passwords can be changed administratively without affecting the keys.
I don't know about recent incarnations of Windows but traditionally the file names are stored in clear in EFS; I see this as a huge disadvantage.
The problem with the propagation of the "encrypted" attribute to mostly any NTFS filesystems where you copy files to can't be underestimated. Probably well (security-wise) intended the problem is that users copy files to external drives and are somehow under the impression that having the external drive itself is enough to have access to the info on it. The problem can be from annoying (copy files from computer A, can't read on computer B) to full-scale disaster (make regular backups on external drives, test them in an uninformed fashion by browsing around and opening random files, have hdd crash or windows reinstall - poof all your files are gone, including the ones from the untouched hdd in your safe).
And of course any solution that encrypts a bunch of folders on a windows machine is bound to be incomplete with info leaking everywhere. Even if you are scared to have obvious encryption on your machine I would still recommend truecrypt (system/full) disk encryption. You can customize the password prompt to your liking (or have nothing at all, just looks like system has crashed/locked up), you can install multiple OSes and boot by default in an unencrypted one, you can have the decoy encrypted OS and so on.
User maintains more than a dozen sockpuppet accounts on Slashdot.
Isn't Windows's own Encrypting File System feature designed to do this very thing?
Yes, and it's been around since Windows 2000. It's hard to believe that someone posting on Slashdot (and the Slashdot editors) didn't know about this.
And to cut off any other similar questions, Windows has also included the capability to play music and video files since at least Windows 95.
"Preferably Open Source".
It's built into the OS, so it's as open source as any other part of Windows. If open source is that important to you then you probably won't be using Windows anyway. Besides, it's pretty clear that the OP didn't know about EFS, and so was thinking about third-party tools. I think the standard in that case might be different.
Wrong! The code is non compilable, so even if you have said windows source code, how are you to know that it is the source code of the binaries running on your system.
You don't.
One of the keystones of open source security systems is that you can build your own binaries from the sourcecode that you reviewed.
I suppose you mean to imply that TrueCrypt makes your computer slower. I suppose that may be true, but I haven't noticed it. TrueCrypt seems to be very, very well designed.
/q command line
option very well. That's very minor, a problem not even in the program itself.
(Yes, I suggested a re-write in the TrueCrypt forum, and yes, I offered to do
the re-writing myself.)
Note that there are TrueCrypt versions for both Windows XP and Vista, Mac OS X, and Linux. All are free and open source.
Because my hotkey script contains a password, I've installed AutoHotkey in an encrypted TrueCrypt container. (A TrueCrypt container is either a file or an entire partition.) So, every time I use a hotkey, the system must get it from an encrypted file and be decrypted. I don't notice any difference in speed between that and when AutoHotkey was installed on an unencrypted OS partition.
I've used TrueCrypt for years and had no problems with it. Most software has numerous shortcomings. The biggest problem I can think of now with TrueCrypt is that the documentation doesn't explain the
I haven't yet experimented with encrypting the entire OS partition. I have experimented with encrypting an entire data partition; I didn't notice a speed difference. However, I found that it is better not to encrypt data partitions, it is easier to make an encrypted container on the data partition. That's especially true if the container can be the size of one DVD, 4.7 gigabytes, less the space necessary for the unencrypted TrueCrypt software. Then you can just dismount the container and burn a DVD backup of the container file and the TrueCrypt software.
TrueCrypt has been 100% reliable for me. There has never been a hint of a problem that might cause loss of data.
TrueCrypt developers: TrueCrypt is a wonderful gift to the world. Thanks!
My opinion is that it's necessary that encryption software be open source; I would never run proprietary encryption software because of the possibility that some rogue employee installed a back door. Also, the U.S. government believes it can force U.S. commercial companies to install surveillance functions in both hardware and software; executives and employees who disagree can be put in prison secretly. I suppose that isn't done very often, but like everything a government does in secret, there are unintended consequences. One of the consequences is that in some cases it may be considered unsafe to use U.S. products. It isn't only the U.S. banking system that is out of control.
Also, since I mentioned AutoHotkey, I will say that it is excellent, although the programming language is a bit quirky. My main AutoHotkey script is now 1563 lines; I use it a lot. It is Windows only.
AutoHotkey is great for Hotkeys and also open source and free. If you want to run scripts that interact with a Windows GUI as though someone is moving a mouse and typing at a keyboard, then AutoIt is better. AutoHotkey and AutoIt co-exist perfectly. The two had a common origin.
TrueCrypt encrypted containers can be formatted as NTFS or FAT file systems. I haven't tried other file systems. All the Windows file system utilities work perfectly inside TrueCrypt encrypted containers: Windows Explorer, ChkDsk.exe, FsUtil.exe, Format.com, and Defrag.exe. I've found the free open source JkDefrag to be a better defragmenter; it works perfectly inside TrueCrypt containers.
Truecrypt has a whacky license (http://www.mail-archive.com/distributions@lists.freedesktop.org/msg00270.html ), so you are better off with FreeOTFE which is dm-crypt compatible though it may not encrypt everything.
It's the same thing with proprietary RAID systems - you barely the layout of the data on disk, so if your array dies, you have to get one that is equivalent. Nice vendor-lock in, and truecrypt is similar.
What is wrong with the TrueCrypt license?
Quoting from the section about making your own modifications to TrueCrypt and calling it by a different name: "Note: TrueCrypt and the TrueCrypt logos are trademarks of the TrueCrypt Foundation. The goal is not to monetize the name or the product, but to protect the reputation of TrueCrypt, and to prevent support issues and other kinds of issues that might arise from the existence of similar products with the same or similar name. Even though TrueCrypt and the TrueCrypt logos are trademarks, TrueCrypt is and will remain open-source and free software."
Basically, the license says, "You can do anything you like except 1) engage in fraud using the TrueCrypt name, and 2) make TrueCrypt code non-free."
If there is anything objectionable, I don't see it.
"The OP is asking for something similar on Windows but that's much trickier on NTFS and Windows for a variety of reasons..."
Good points.
It is necessary to encrypt the entire Windows OS partition. That's because Windows scatters files everywhere. For example, on one installation of Windows XP with I seem to remember 4 users, I found that temporary files were stored in 47 locations.
That just begins to describe all the scattering. Commercial programs store files in lots of places. There's a lot of stuff stored in the Windows registry files.
Windows file encryption should not be used. It has extreme shortcomings. Many people have lost their data because of Windows file encryption. This information has been verified by several Microsoft technical support people.
NTFS supports per file or directory encryption using a key stored as in the domain controller (or locally for non-domain systems) encrypted with the users password.
Works very well in a domain/activedirectory enviroment as the key is also available to domain administrators if data needs to be recovered due to a 'lost' employee.
Just right click on your home directory in Explorer. Select Properties->Advanced, and check the 'Encrypt contents to secure data' checkbox. When you click OK it will begin encrypting all the files and subdirectories. Any new files created will be created encrypted. If you cancel the conversion process, files that it didn't get to will remain unencrypted, but new files will be encrypted. So in short, don't cancel the initial conversion :)
It works, no one has found any glaring holes in it, no real reason to use anything else unless you're using one of the bottom end versions of Windows that don't include it.
Persistent Volume manager for Kubernetes - https://github.com/dwimsey/openshift-pvmanager
If an administrator changes your password the administrator can still access your files as ActiveDirectory stores a copy of the encryption key for administrator usage in just such cases as you describe.
You can encrypt to a USB thumbdrive and use the data on multiple machines within a domain environment just fine as long as you always are using a login with access to the encryption key, such as the original encryptor or an administrator account.
Personally, as someone who works for a thumb drive manufacture, I wouldn't worry about encryption on your thumbdrive, its likely to fail before anyone can do anything useful with it anyway! (J/K of course, we only sell the drives to peddle our encryption software, but thumbdrives are extremely unreliable none the less :)
Persistent Volume manager for Kubernetes - https://github.com/dwimsey/openshift-pvmanager
You know, I see this sort of thing all the time with TruCrypt and I have to ask ... Short of a few government agencies and a few paranoid dorks, who the hell uses this? It can't be used on a server unless you want a reboot to cause the server to require a human to fix it, so its really only useful to end users, more specifically laptops. In which case, if your data is THAT important, why the fuck are you carrying it around on a laptop in the first place?
This is just ridiculous. Its great the TrueCrypt does it, but anyone who actually needs it is probably going to use a different more obscure method, just to make it that much harder to bypass.
I guess maybe its the audiophile cryptographers who need to encrypt their laptops so no one realizes that their $1500 headphones and Monster cables are bullshit and sound the exact same as my $10 pair after you've heard the same sound effect 30k times while playing F.E.A.R. ...
Persistent Volume manager for Kubernetes - https://github.com/dwimsey/openshift-pvmanager
If you use NTFS, it already supports encryption all the way down to the file level.
This is not a good faith question. Nobody is going to waste their time writing an open source extension to a proprietary operating system that duplicates the functionality of the core O/S. And if they did the result is probably not going to be worth using because nobody with sense is going to use and test it.
What this amounts to is that the slashcrew will post pretty much anything that panders to their biases and so they will post without thinking a question that is clearly designed to provide the answer 'no'.
Same thing happens on the camera forums. For years Canon fanatics used to appear in Nikon forums to ask about full frame sensor cameras. Then Nikon came out with a model that beat the Canon and then some and they started asking about fast prime lenses. Now that Nikon have started releasing a new range of fast primes they are asking about constant aperture f/4 zooms. None of it makes the slightest sense. Very few professional photographers would regard the Canon lenses as superior to Nikon in optical quality and certainly not in range. The Canon super-teles were much better at focus speed at one point because Nikon had their heads up their butts with their insistence on only putting the motor in the camera. But that changed long ago.
This type of question is not helpful unless what you really want to do is to have an argument for the sake of it and fix the terms of debate so you are bound to win.
At this point we have five windows boxes, three macs and a Linux box operating in the house. Of the nine machines the Linux box was by far the hardest to get running because the geniuses at Ubuntu decided to write a 700Mb distribution on a format with a maximum design capacity of 650Mb.
There is plenty of stupidity to go round. If people want to take pot shots, Linux is just as open to stupidity as anything else. When someone makes a similar attack on Linux the response is typically 'but these people are volunteers'.
Windows has this feature built in, end of story.
Looking for an Information Security student project suggestion?
Try http://dotcrimeManifesto.com/
n/t
If an administrator changes your password the administrator can still access your files as ActiveDirectory stores a copy of the encryption key for administrator usage in just such cases as you describe.
Most home user machines are standalone XP Home, so there is no backup of the users keys stored in AD, in that case.
That would be a considerable flaw, in that the backup is only available to some users...
Windows might be doing better at keeping user data within user directories, but users aren't... Of course, the answer is to not let them have write permissions to those directories, but then janky app developers would have to follow some kind of quality control to make sure their apps run without local Admin permissions.
If someone alters your password not through the normal password change process (i.e. an Administrator uses 'reset password'), you lose access to your private keys, and thus your encrypted files.
You can mitigate this though by backing up your EFS certificate, which is recommended.
http://technet.microsoft.com/en-us/library/cc756891.aspx
In Windows most user data is stored under Documents and Settings but misbehaving applications may put it elsewhere . On Linux all user data is always under /home, which is typically a separate partition either on the same physical media or another storage medium or mediums. Therefore, if you want to protect your data rather than the OS itself:
Guns don't kill people; Physics kills people! - John Lithgow as Dick Solomon on Third Rock From The Sun
Usually a reboot on a server DOES require a human to fix it. But yes, it's not intended for servers because they tend to be pretty well locked up (unless it is your home server and you'll be better off running Linux anyway and in any case it doesn't matter if the server goes down until you go home and can enter the password).
The UK government loses laptops by the thousands, truecrypt would do a lot of good here. The argument that you shouldn't carry the data on the laptop is moot as some users have only one computer. Even if you don't have tons of secret documents you still have some pictures, some IM accounts, maybe some bank info in your browser cache and so on. Are you trying to say that you just don't care if somebody has access to your notebook? Can you give me access to have a look?
Also there's the case when the disk breaks under warranty. I understand you buy another desktop which you keep secured so you don't keep private data on the notebook but what do you do when the disk on the desktop dies and you still have warranty? Destroy it physically (and take a loss because otherwise you would be entitled to a replacement)? If you have it all encrypted you just send it back without worries for what info has your computer ever saw.
The installation is a breeze, the performance hit and other disadvantages are minimal and the OP obviously wants to bother with encryption. What's the problem then?
How about displaying transparent PNGs? Or properly rendering CSS?
Admittedly, I've been out of the loop for a while. You may have upgraded information.
TrueCrypt + TCGINA to provide an encrypted user profile. Although, this might not be supported by the newest version, which already offers transparent whole-drive encryption for Windows now.
You can always use TrueCrypt whit its vast list of encryption algorithms, what u do is you create an encrypted partition and redirect my documents folders to that partition. And vuala. There u have it. Or u can create an encrypted file container and redirect all your documents there. Its open source, itâ(TM)s free and it works.
There is an unresolved issue with EFS interacting with Indexing services, such MS's new indexing search. When you combine those two with some of the new Anti-Virus application version it will corrupt the files that are encrypted.
The multiple computer problem in a domain is solved by setting up a PKI through certificate services. This combined with a logon script to encrypt the profile directory takes care of those problems. If you are doing EFS on a large scale in a domain you would be crazy not to use a PKI. Another advantage to this is should the certificate get lost you can set recovery keys that a admin can use to decrypt the data.
This can also in a windows domain be used to create bitlocker keys as well which encrypts the entire system.
It does not matter if your solution to encrypt your user directory is Open Source: Much of the underlying operating system is closed-source, a system which you cannot audit and which you cannot find a reason to trust. You should perform a web search on the string "_NSAKEY" to help your understanding of the issues underlying why you should not trust your data storage and encryption to any network-connected installation of any modern Microsoft operating system. If you need reliable security, you should be using an operating system booted from CD image on a non-networked PC and TrueCrypt. You don't know what the OS is phoning home, you don't know what kind of backdoor or weakness the Microsoft encryption engine module is introducing into your data (unless you have the skills of a cryptanalyst or are working for the NSA with a need-to-know and a security clearance) and you also don't know what the hardware is phoning home or squirrelling away in some NVRAM somewhere, waiting for a forensic analyst to recover.
Your requirement that one part of the chain be auditable does not mean that the other, non-auditable portions, are secure.
I used CFS (from AT&T research) some 15 years ago. CFS was an early effort based on the NFS protocol, providing a server (trusted, run by you) which would hold your keys and re-export an encrypted directory in plain text for you to mount locally. It was quite useable.
"I now encrypt all my systems fully."
You didn't say what encryption software you use.
Don't.
Foolhardy, you apparently don't realize all the problems with EFS. It's mostly for use with a domain controller, for example.
That only works if you are connected to a domain controller. If you aren't, there are very serious problems. If your OS becomes corrupted, you lose all your EFS data.
Pointless argument. XP Home does not have EFS
Noone really uses XP Home, except total newbies, due to the various ways in which it is crippled.
The group that are most interested and knowledgeable enough to specifically ask for home directory encryption are technical enthusiasts.
Who normally run XP Pro; however, that doesn't mean they'll fork over the extra few thousand bucks for a server and a copy of Windows server standard to setup a home AD environment.
You obviously didn't read the entire thread. The problem occurs when a computer is detached from a domain, or not part of a domain.
Most companies consider the documents written by their employees during work as proprietary.
Minutes from meetings with suppliers or customers, code written on the train by commuters and reports written to your managers in that quiet moment on the plane are all examples of data that should be encrypted.
Of course, good crypto should not be an excuse to download the entire customer database to your laptop.