I have been having trouble with Solidworks regularly having buttons or keyboard shortcuts stop working.  I have to restart to restore functionality but it is quite frustrating.

I open Solidworks and it is fine but after some time, maybe 1/2 hour or more, some of the buttons stop.  Things like my keyboard shortcut to rebuild, or save stop working.  Sometimes the ribbon buttons get greyed out unexpectedly.  Even things like right clicking on a part in an assembly and clicking open does nothing.  The "Open" command is there but clicking on it doesn't work.

I just wiped the Solidworks registry so that it rebuilt but the problem persists.  Any ideas?