Last week I installed iOS 5 beta 1 without any problems.
But I downloaded the beta from a different developer account than my own. So i signed up and paid for my own account yesterday.
I then added my iphone udid to the device screen here
http://developer.apple.com/ios/manage/devices/index.action
After that I downloaded the latest itunes beta (10.5 v2) and latest iOS 5 beta 2 for my phone and tried to do the Option+Restore to update my phone.
but it didn’t work and I got this error message.
Any ideas or suggestions on how to fix this ? email me at bsabet at gmail or @bijan on twitter.
Many thanks!
update: John Minnihan helped me figure this one out with a pointer to this link. thanks John!