I had this problem too yesterday when i tried to play GT5 after a month or two not playing.
It occured immediately after i updated to 2.00 and tried to play. The same error message appeared.
It did the following:
- copy gt5 savefile to USB (btw, my savefile size was approx 1900 - 2000 kB)
- delete the whole gt5 install file (which was 20GB)
- reinsert gt5 disk and re-update all updates up to 2.00 (with all updates immediately after one other)
- then install the game in order to save loadup times etc. (the usual install game thing)
- Checking whether the game loads, an autosave got created automatically
- Exit game, and copy the previous savefile from USB to the PS3. When asked whether to overwrite the existing savefile (which got created automatically, see one step before), i choose 'yes'.
- Start up game again
- Profit
i have tried this with a few other people, it did not work. I believe the reason is your save file was not corrupted when you saved it. in our case, the file was already corrupted. If you have an older save file you can do the steps you just mentioned and it will work until a certain point is reached. Eventually it will happen as before. Your very lucky or smart you saved before it was to late