Hi,
We have seen this situation before as well when doing upgrades.
In our situations, the access error resulted from an incomplete resultant set of styles and definitions files. How we resolved was to copy the complete SD*.sam files from the AR sample data (\softrak\receivables\samdata) and replace the live SD files in your data folder.
Suggest that you cut out the live SD*.dat files before replacing and putting into a backup folder, and carefully restore these files when you get the access message in AR resolved. Your consultant should be able to help you with these tasks.
Not to say that the Hot Fix solutions and roll backs will not work, but we have had success with this other resolution before the said hot fixes were available.
Best,
Brian