Outlook 2007 "Could not install the custom actions. The object could not be foud"

If you're getting the message "Could not install the custom actions. The object could not be found." in Outlook 2007, try deleting frmcache.dat. On Windows 7 and Vista it is found in:

C:\Users\USERNAME\AppData\Local\Microsoft\FORMS\frmcache.dat

On Windows XP it should be located in:

C:\documents and settings\USERNAME\local settings\application data\microsoft\forms\FRMCACHE.DAT

Note: The file is a hidden system file.