Paul, that was the problem. I disabled Malwarebytes, and the problem went away. Not wanting to exist without the protection that I get from MB, I read further.

On MB's web site, I found this:

Websense Endpoint hooks KernelBase!LoadLibraryExW API via QIPCAP64.DLL. MBAE also hooks this API. However due to a bug in Websense's hooking mechanism it improperly handles the hook and may create crashes when opening Word, Excel or other applications. If you are experiencing this issue please contact Websense to report this bug to them ("bad attempt to copy jmp qword instruction rip based"). We are working on a new mechanism to handle these types of conflicts.

Further experimentation proved that if I simply turn off Anti-Exploit (MBAE) instead of all of MB, Word works perfectly. It does appear, though, that the problem is with Websense Endpoint, which I didn't even know I had on my PC.

As long as I can toggle MBAE on and off when necessary, I'll wait for MB to release their "new mechanism."

Thanks for all your help. Problem solved!

Tom