I met this error when I open email -
Could not install the custom actions. The form cache file c:\users\xxx\appdata\local\microsoft\forms\FRMCACHE.DAT is not valid content your administrator.
Go to Control Panel, Open folder options, select view tab, down the you will
see a hidden files and folder, Select show hidden files and folders.
Close the control panel.
Open my computer and search down the directories.Local Disk (C>Users>(your user name)>AppData>Local>Microsoft>FRMCACHE.DAT
Delete the folder named FORMS, its corrupt!
Close the window and open Outlook 2007, everything should work fine now.
