Go to this post and download the fix:
P.S. If you want to clear the previous installation from your computer:
1. Go to
Start and click the
Run... button.
2. Type
regedit.
3. Go to
HKEY_LOCAL_MACHINE\SOFTWARE\Sega\Medieval II Total War\Mods\Unofficial and delete the
kingdoms grand campaign mod folder.
Or download the
CCleaner (it's a free software)
After installing it go to the
Tools and click on
Uninstall button. You will wind the KGCM in the window. Click on it and choose
Delete Entry.
After deleting the registry you'll be able to install the mod from scratch.