If you look through Déjà Vu's log files and find mention of the error message:
Could not find installable ISAM.
Your installation of the Jet Database Engine 4.0 Component of Windows may be malfunctioning. You should re-install the Engine.
Once you have done this, you must register the Mstext40.dll library. To do this you must first locate the file. You can do this opening a command prompt and in it typing the following commands: