Try to delete some files from KORE 2, which will be rebuild once you open KORE 2 again. In order to do this, you might need to adjust a setting on your computer.
Please go to "My Computer" and click on "Tools" in the taskbar, then select Folder Options>Go onto the "View" tab. Under "Advanced Settings" scroll to "Hidden files and folders". Enable the option "Show hidden files and folders" and press "OK".

Then please go to the following directory on your computer:

on Windows XP:
C:\Documents and Settings\~username~\Local Settings\Application Data\Native Instruments\Kore 2

on Windows Vista:
C:\User\Username\AppData\Local\NI\Kore2

Delete all files except for the "Database Cache" folder and its content, means delete:
Factory.kdb.cache
koredb
Pluglist
User.kdb.cache
Empty your trash and start the KORE 2 software again.