Videos on Drive

Some users report Videos uploaded from Drive and embedded in their Site do not play, particularly if not signed in to a Google Account. This seems to be a common issue for Google Drive users. It does not seem to be a Google Sites embedding specific issue but a more general Google Drive issue.

A quick search yields a lot of reports and potential solutions.

I was having this problem myself using Chrome and I discovered that by going to chrome://settings/content/cookies and click the 'Add' button next to 'Allow'adding [*.] to 'Allow' fixed the problem for me.

Until Google Drive fix this issue, I think Sites users are better advised to upload their videos to Youtube or Vimeo and embed from there.