What is a .wmv file?

You have a WMV file, probably from the mid-2000s. It came from a webcam, Windows Movie Maker, or a download from an era when Microsoft thought it could own the video format space. WMV was everywhere during the Windows XP and Vista era — bundled with Windows Media Player, used as the default export format for countless consumer tools.

Then the world standardised on MP4 and moved on. WMV uses Microsoft's proprietary codecs and has minimal support outside Windows. macOS struggles with it. Phones ignore it. Web browsers pretend it doesn't exist. The format is technically fine — it compresses reasonably well and the quality is acceptable — but there's simply no reason to use it when MP4 plays everywhere.

Windows Media Player still handles WMV natively. VLC plays it on every platform. If you have a collection of WMV files from old projects or webcam recordings, they still contain your data — convert to MP4 with fwip to make them usable on modern devices. The conversion preserves the content while giving you a format the rest of the world recognises.