Memory full..
If you've been using (watching tv) with a viewsat ultra, the guide takes up a lot of available memory and trying to load a new file with the memory full is your downfall. It's as simple as a hard reboot from the rear switch before loading any new files. This "dumps" the memory and allows a smooth software update. This reboots the unit and allows much more available memory. Do this before loading any new files, and you'll never have a problem.

If you didn't reboot your unit and it's stuck on the "Caution" screen, you'll most likely have to load a factory file on it using the null modem cable to get it back working again.