move office to new pc

ThemeOne

Two things you could try - activation backup utilities, and phone Microsoft.

The activation backup utilities claim to be able to copy the activation from one computer to another without you needing a key. If it works, it would be just what you need. I think I did it once in the distant past successfully. The one I used was called Microsoft Toolkit.

I've never tried phoning Microsoft so can offer no personal experience, but I've often heard it suggested that they can be surprisingly helpful in genuine situations such as yours, particularly if you're not a business. I guess the worst that can happen is they say you have to buy a new key.