What type of video files can be uploaded/attached?

You can upload it here if its 60mb or smaller.

How big is the video?

See the video cam icon in the toolbar, click it, then upload mp4 or any should work.

I thought you said at first it would let you but it was too big?
No, I tried many different file types I converted into those listed above. It reduced file size dramatically. That is not the issue.
Just tried from my phone. The dot MP4 file, This is the neassage I got. "OOps, We ran into some problems. The uploaded file was not a video as expected"
Ok, now in google browser. Will try again. Tried it. After uploading, got back message..."Oops, something went wrong. The uploaded file was not a video as expected."
Ok, I will try it on my android tomorrow, I can't now my phone is dead and charging.

This is from my android, it uploaded fine on android
Now on android when I clicked the video cam icon it asked where I wanted to get the video file from, it gave me 3 choices, from the phone, from the camcorder and from files, I choose files and upload this video from my google drive, which I have the google drive app on my android as well.:)

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