How do you fix it when you get error Code: Too many Activations?

I am getting the following error code when I try to transfer books to my Sony PRS600 Reader using Adobe Digital Editions.  My Operating System is Windows XP.   Please help.  I have called and got representatives who did not understand or we had a problem with the language.  I have tried the "Self Help" steps and they don't work.  I just need to have the "ReActivate" so I can continue to download and transfer books.  The customer service system for this problem is terrible.

E_ACT_TOO_MANY_ACTIVATIONS http://adeactivate.adobe.com/adept/Activate 410:12000:8390 urn:uuid:22aea7ea-cbf3-45e3-ba16-bd9b929291fd