Worksheet Command Button will not work
 

One day all Command Buttons embedded on worksheets quit working for me. I
click on them and nothing happens. At the same time I noticed that in saved
workbooks and in brand new workbooks whenever I try to put an object from the
Command Toolbox on a worksheet I received the error Cannot Insert Object.
I've searched Help, various Excel forums, looked at every menu item and I can
not figure out why suddenly worksheet embedded objects quit working for me.
Assistance will be greatly appreciated.