SW2013 SP3, Windows 7 x64

I have one user for whom the right click menu on Edit Material icon in the feature tree does not work correctly.  Instead of the usual items in the pop up menu:

This user sees only the last three menu items:

Hide/Show Tree Items...

Collapse Items

Customize Menu

Clicking on Customize also shows only the last three items.  We have 10 identically configured machines and this is the only one where the problem has occurred.

As a stopgap measure, I have added the Edit Material icon to a toolbar, but I'd like to get this problem fixed.

Has anyone else seen this problem?

Jim S.