Can't import video !

I am having trouble getting video to import into Sonar PE 8.3.1.  It does not work with any file type.  Files all work in any of the video players.  Runnig on a PC with Vista x64.  I keep getting the error message "Unable to import video - Unrecognized file format or invalid file. No combination of intermediate filters could be found to make the connection."  I am working with .mpg files but I have tried .avi files and they don't work either.  Any suggestions?