Files With WMV Extension

If you do a Google search for WMV, you'll find out about Windows Media Video.

If you are worried about rogue files, be sure that you have disabled "hide known file extensions" in Windows Explorer, because an old trick is to name a file like this: Bikini Babes.wmv.exe or cute-kitty.jpg.exe - an incautious or inexperienced user might not realise and double click the file icon and it would then be too late.