Admins Accuse Microsoft of Hotmail Cap

kurmudgeon writes "The Register is fielding reader tips that Hotmail has placed Draconian limits on the number of Hotmail recipients who can receive an email. The first 10 Hotmail addresses included in a mass email go through just fine, according to these reports. But any additional addresses are returned to sender with a message that reads: "552 Too many recipients." (Microsoft denies it has placed any such restriction on the number of senders.) This would appear to be a violation of RFC 2821, which states: "Rejection of messages (for excessive recipients) with fewer than 100 RCPT commands is a violation of this specification."

Comments

And the problem is...?

[Kelson]

Let's look at that phrasing: "Rejection of messages (for excessive recipients) with fewer than 100 RCPT commands is a violation of this specification." (emphasis added).

Are they rejecting messages, or are they rejecting recipients?

According to this, they're rejecting recipients with an obvious "try this again" code. Really that should be 452, not 552, but that same RFC 2821 says that senders should treat a 552 as temporary:

RFC 821 [30] incorrectly listed the error where an SMTP server exhausts its implementation limit on the number of RCPT commands ("too many recipients") as having reply code 552. The correct reply code for this condition is 452. Clients SHOULD treat a 552 code in this case as a temporary, rather than permanent

So whatever sending server runs into these limits should retransmit the message to the remaining recipients on the next queue run. Okay, it'll only reach 10 recipients at a time, which is annoying. It shouldn't be kicking back the error to the client.

Really, assuming Microsoft has actually put this limit in place, the only thing I can see that's wrong, from a practical standpoint, is using the outdated 552 code instead of the more specific 452 -- but that same RFC people are waving around says that their servers should treat it as temporary anyway.

Am I missing something?

Re:And the problem is...?

[Obfuscant]

No, according the standards, every recipient rejected for "too many" stays in the queue and delivery is attempted at the next queue run. While Hotmail's violation of the standard seems bad, the worst effect it should have is to slow the delivery, not prevent it.

If a client actually stops trying to deliver based on a 552 error, then it, too, is violating the standard, in a way that actually prevents delivery. I consider that a more serious violation.

Hotmail is unreliable anyway

[Anonymous Brave Guy]

Our (100% legitimate, double opt-in) mailing list gets a few Hotmail addresses added to it every now and then. We frequently get people complaining about missing mails and so on. Invariably, it's because of something silly, usually spam filtering that has been set to be so ludicrously aggressive that practically anything not white-listed (i.e., nothing on a new account) gets through.

We have now reached the point where we consider Hotmail an irrelevance. We don't even advise complainants to use another mail client any more, we just ignore them. The list is not run for profit, and the effort of supporting Microsoft's not-playing-ball freebie mail system just isn't worth it for what is basically a hobby set-up run for the benefit of our community.

Re:E-mail is dead for mass communication

[RollingThunder]

I take it you're not on any discussion mailing lists, then?

All MS is doing is cranking up bandwidth costs now. Instead of one copy being sent to all 68 subscribers on the server, my listserv now has to send them 68 copies of the same damned thing. Incredibly inefficient, but the subscribers want the email, so that's what'll happen.

What's the bid deal?

[jtroutman]

There's been a fix for this problem for a while now.

Dont worry!

[Ariastis]

No sweat guys, for 19.99$ per year, you can become a member of the Windows MSN Live Hotmail Benefactor Plus Live rewards program!

Benefits include :
1) Spam whomever you want, bypassing all spam filters!
2) Send e-mails to more than 10 recipients (Also called the "I run a mailing list you fucktard" option)
3) Free "Upgrade to Vista (Please)" coupon.

I'm not TERRIBLY pro-MS, but...

[DigitalSorceress]

Honestly, if everyone followed all the RFCs for email and didn't adapt, spam would probably bring everything to a grinding halt. As it is, with countermeasures and counter-countermeasures in an escalating spiral in the "spam wars", I sometimes marvel that email even still works at all.

Granted, security through obscurity isn't really effective, but why should they bother telling spammers how small to make their batches in order to get things through? Make the bastards work a little bit.

Wow, I've gotten cynical.

RFC 2821 is not (yet) a standard

[Eric Smith]

This would appear to be a violation of RFC 2821, which states: "Rejection of messages (for excessive recipients) with fewer than 100 RCPT commands is a violation of this specification."

RFC 2821 isn't a standard, though. It's on the standards track, but it has not yet been accepted by the IETF as a standard. The current SMTP standard is RFC 821, also known as STD 10. RFC 821 says:

recipients buffer

The maximum total number of recipients that must be buffered is 100 recipients.

TO THE MAXIMUM EXTENT POSSIBLE, IMPLEMENTATION TECHNIQUES WHICH IMPOSE NO LIMITS ON THE LENGTH OF THESE OBJECTS SHOULD BE USED.

This only requires that up to 100 recipients must be buffered, but doesn't explicitly state that there is any requirement to deliver to all 100 such recipients, nor that recipients cannot be rejected for some reason other than running out of buffer space.

Re:Hotmail has many worse problems than this one!

[saarbruck]

OP could have provided more detail but was not trolling: I run an email server on a static IP on my 768/128 DSL line. It's for 2 users. My mother, who has been a Hotmail user for so long that she can't relocate or "no one will find her!" refuses to move to gmail despite my pleas. Hotmail silently drops mail from my server about two thirds of the time. Messages such as "Hey, where are we meeting for Grandma's birthday dinner" disappear into the ether despite me being on her whitelist. Repeated hotmail support requests go something like this:

me: why are you accepting my email with code 250 OK, but never delivering it?

them: we can't talk to you until you submit all the forms at postmaster.hotmail.com

me: submits the forms, which are clearly geared toward businesses (my "site" doesn't have a "privacy policy" or an "opt out form" because I don't SELL ANYTHING).

them: we can't talk to you until you sign up for our email tracking service to analyze your traffic

me: signs up. My server doesn't generate enough traffic for them to even log.

them: you need an SPF record

me: installs an SPF record

them: your SPF record is wrong. RFC blah blah states...

me: IT WAS GENERATED BY YOUR ONLINE TOOL!! And if you want to quote RFCs at me how about the one where if your server accepts email, you're guaranteeing not to drop it for frivolous reasons (RFC 2821, sec. 6.1)?

them: our reasons are not frivolous, but we won't tell you anything.

me: like how your servers drop email sent from thunderbird but let the same messages through when sent from outlook express?

them: we don't filter based on header information

... and so it goes. I understand that I'm a small fish in a big pond and that there's a war on terror, uh, I mean spam, but hotmail just sucks.