How to Play M4V Files in Windows Media Player
The Windows Media Player (WMP) is configured to play a set number of video file formats. Play the M4V optimized video file format on WMP by downloading a video plug-in. The video plug-in will enable WMP to recognize and play the M4V file. The procedure requires the use of a web browser and does not cause any interference with WMP's abilities to play the other video file formats.
Launch the default web browser included with the Windows operating system by selecting it from the "Start", "All Applications" pop-up menu.
Go to the Microsoft Windows Media Plug-in website. Download a plug-in that is compatible with the M4V video file format to the PC's desktop.
Double-click the file once it has downloaded. Follow the menu commands to install the plug-in into the Windows operating system so that Windows Media Player can acknowledge the M4V video file format. Restart the PC after the installation is done.
Launch the Windows Media Player program by selecting it from the "Start", "All Applications" pop-up menu. Click on "Open file" from the "File" drop down menu at the top of the program.
Navigate in the window that appears to the M4V file. Double-click on the M4V file to load it into Windows Media Player. Click the "Play" button at the bottom of the Windows Media Player program's screen to play the video.