Thanks re the license advice. I wasn't aware of this since Office was a birthday present from someone else and I don't know the source. I would not have posted the photo if I had known. I will consider whether to uninstall it soon or allow it to run until MS deactivate it.

I may install Libre Office alongside MS Office so that I will be able to get used to it first just in case MS deactivate it.

My MS Office is 32-bit, which I think I am best staying with rather than potentially cause problems by trying to change it to 64-bit. After your advice I do not want unnecessary communications with MS servers.

I'll also try disabling hardware acceleration if it should happen again.

Thank you again.