I appear to be unable to open any kind of video file in Photoshop CS6, I always get the error message "could not complete your request because it is not the right type of document".
I have noticed, however, that a couple of things seem to be different from all the video tutorials that are out there, e.g:
1. The Timeline dosen't seem to give me the option to open a file from it and appears to be a timeline for animation only (see image below)
2. The Mini Bridge dosen't show the movie files, e.g. on my desktop I have three different movie files (AVI, MP4 & MOV) and as you can see none appear (see image below)
Could you post your system info from Photoshop's Help > System Info dialog?
You should be able to see video files, open them, and be able to create a video timeline.
Other users haven't had these trouble mostly, so curious what's going on here.
Also, if you have an image open, you should be able to switch timeline modes by clicking the "convert to video timeline" button which is to the left of the play controls and looping options.
Are you going to the motion workspace and then clicking "create video timeline" and then clicking the + on the right side? If you do that then it will open a dialogue box called "add clips" where you can browse for your video. Let me know if that works for you.
That's odd - while the system info looks right, you're missing several of the workspaces that ship with Photoshop CS6, and some icons from the timeline palette.
You're not seeing the "create timeline" button because you're opening something that is already an animation. But it looks like you opened a single frame image, or an animated GIF with a single frame instead of a video.
I'd almost think you're running an older build of Photoshop CS6, from long before the public beta.