Despite its former problems, when the ICS update started rolling out to the Transformer Prime earlier this month, users were elated. However, some users were immediately hit with a problem while trying to update: serial number not found. This error, as simple as it sounds, completely prevents the Prime from being able to perform any sort of update, be it manual or OTA.
ASUS is aware of the issue an working on a fix, but in the meantime, our beloved dev community has been cooking up something of their own, and it looks like it's ready to go. The fix is called Ratchet and it basically rewrites the configuration partition, allowing the user to manually enter serial number.