Getting error with right click after selecting multiple cells with Ctrl

dnacpil 

I am having the same problem with a worksheet that I have used CTRL + multiple cell selection.

as soon as I right click to bring up selection window ( I'm trying to clear contents ) I receive the same error message.  I click okay on the error message and it comes up again... so I click okay one more time and then I am finally able to bring up the selection window and select clear contents.   This is a new problem I've encountered this week.  I'm unsure if this is due to a Microsoft update or my company computer update ?