If you like to rotate videos in Windows Media Player you can NOT
If you like to rotate videos in Windows Media Center you can NOT.
So how can you rotate a video?
Here are simple things to try for rotating your desired videos:-
Open Windows Movie Maker
Drag and drop the video into the blank area on the right side or,you may add video by clicking Add videos and photos.
Now click on the Rotate right 90 ° or Rotate left 90 °
Save movie as WMV file.
Now you can open the rotated video in Windows Media Player also.
If you have VLC Player:-
Open the video,go to Tools >Effects and Filters > Video effects
Put a tick mark against Transform option
Here you will find to rotate videos to 90° ,180° ,270° ,flip horizontally or flip vertically options.