I don't know if I'm doing something wrong. I bought OD months ago and I didn't even know it could be upgraded. Anyway, I downloaded StarDock Central and I went to the Info thingie, I entered all my information including my serial, and I got that message. I clicked on Lookup Serial Number and I got an email with the same email and serial I've been entering. I even copied it and pasted it from the new email, and I made sure there are no spaces anywhere.
I don't know if I'm selecting the right thing or not. I'm trying to update ObjectDock Plus 1.90 - 535u. Here's a pic:

Firewall is not blocking anything because I was able to request my serial by clicking teh Lookup Serial Number button