Thank you :)

I really don"t know how to help you with the nag screen but maybe email office support I just recently came back to windows 10 after years using a few iMacs

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Do you pay monthly for Microsoft office I pay the monthly fee and can install it on 5 computers or laptops

Windows Search: microsoft office product key finder

there is one there that includes the office product key

You might go to Softpedia - Free Downloads Encyclopedia click on the windows section in the search box type Windows product key finder that should work