This is the biggest problem that I've encountered with Chrome, limited file support. The solution requires an app to play .wmv files. Keep an eye open in the Chrome Webstore, and an app may show up in the near future. I have a similar problem because I receive graphics and illustrations as email attachments on a daily basis in .zip and .igs formats which I cannot open. My voicemail forwards phone messages to my email as a .wmv files, which I cannot open either. I think building support for these file extensions should be a priority.