Previously, we shared with you guys that a small smattering of Transformer Prime users were experiencing some strange bugs after trying to update their tab to Ice Cream Sandwich. Although Asus hasn't officially acknowledged that there is a problem, they did admit to a separate bug affecting a small group of owners. Here's a quote with some details,

This bug presents itself in the Transformer Prime software which doesn’t allow the OTA update to recognize the tablet’s serial number. You know what that means— no serial number, no dice.
On an official support thread over at XDA, Asus recommends a simple factory reset or reboot to correct the bug, but if that doesn't handle it, they also shared they are working on a better solution. Gary Key of ASUS said they are “very close to finalizing a fix”.

Perhaps this might alleviate some of the other issues, and/or at least spur Asus to develop a more comprehensive fix.

Source: TransformerForums via TalkAndroid