In iTunes Music Store, go to your Account page and it will tell you how many computers you have authorized and provide you with a link to remove all the current authorizations.
Alternately, you can email iTunes technical support and they can de-authorize them all.
Then, just play one of your iTMS songs and it will prompt you for authorization. Enter your information and you're all set!
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In iTunes Music Store, go to your Account page and it will tell you how many computers you have authorized and provide you with a link to remove all the current authorizations. Alternately, you can email iTunes technical support and they can de-authorize them all. Then, just play one of your iTMS songs and it will prompt you for authorization. Enter your information and you're all set!