Unable to Save and Publish an assignment

[holmesl1]

I've created the assignment, checked all the appropriate boxes and tried to "Save and Publish".  The screen goes gray while it works, then brightens but assignment is not published.

[MrVelsey]

I realize this is a few years after the fact, but I had the same trouble.  What finally tipped me off was that I discovered I was trying to save an assignment created for one assignment group inside the folder for another type of assignment.  All I had to do was use the "plus" sign to create the assignment in the proper group folder, set it up and I was able to save and publish it at last.