Reset computer authorizations in iTunes?

[Pink∆Floyd]

How do I reset all of them? Is there any way reset all of them at once without physically going to every computer? There are some computers that we no longer have or have been sold, so that's why I'm asking

 

[alust2013]

I believe you can do so if you go to your account in the iTunes store. If not, email iTunes support about it, and they can do it for you.

 

[Pink∆Floyd]

Thanks