This is quite right - it's a Windows Movie Maker project file. You should ask the sender to resend the file by clicking file>send movie to ...> e-mail in which case it attaches to the email a .wmv file which does play in Windows Media Player. Alan >My guess (having never used Windows Movie Maker) is that the .MSWMM file >would be the equivalent of an iMovie project file -- pretty much useless >outside of the computer it was created on... (without going to great >lengths to include all appropriate source media, etc.)