Ok, a google search solved the problem.
Tool- Options-Edit-Allow cell drag and drop

Why would this have been unchecked?

"Shanx" wrote:

Hello,

This morning i've opened up my excel with a file i was working on yesterday,
and I have found that my "fill handle" is no longer present for any cells
that I select. It seems like a pretty silly question to ask, but it is one
of those little features that makes many things easier.

Thanks,
David