You should be able to manually setup the VAB file types (.LST and .LSS) through the Windows Control Panel. Select Folder Options from the Control Panel, and then select the File Types tab. Then search for the .LST and .LSS file extensions in the list of registered file types. Select the desired VAB file extension, and then choose the 'Opens with' Change option to select which program to use for these file extensions. That should correct the problem. Regards, Steve