Does D2D have an install or download verification tool you could try?
Did you try a clean install of D2:ED and then FoV? (uninstall FoV/D2:ED, reboot, make sure there is nothing left in the D2 folder (saves are stored elsewhere), then install D2:ED and FoV)
I have not seen this error reported before, but Google seems to think it is a Securom copy protection problem. A fix posted in a couple places, from Securom's support:
1) Open the command line by pressing Start and selecting the Run... option.
2) Type cmd and push the [Enter] button on the keyboard.
3) Please type in the following command:
rd /s "%APPDATA%\SecuROM"
and press [Enter] on the keyboard.
4) Answer Y to the Y/N question and press [Enter] to complete the process.
The folder should now be deleted. Please understand that any SecuROM application that uses UserData will rebuild these files and folder with future launches.
This didn't help one person, who still had Securom files from the beta of the same game in their temp folder, and they also needed to delete the relevant folder in the C:\Users\%username%\AppData\Local\Temp folder. There was no public beta of D2:ED or FoV, so that should not be necessary in this case.
In XP the saves are in the folder
C:\Documents and Settings\ %username% \Local Settings\Application Data\Divinity 2\Savegames
or in Vista / Win 7
C:\Users\ %username% \AppData\Local\Divinity 2\Savegames
You may need to set Windows Explorer to show hidden files and folders (
XP, Vista,
Win 7).