I have an old copy of MS Office Pro that I was using on my old Windows 10 PC which crashed. When I tried to install that copy of Office 2010 on my "new" computer it will not validate the product key. Is there any way that I can get this validated? Every time I open one of the programs I get the registration window and I am afraid that one day I won't be able to use any of the programs. I am not a young person and I don't use Office for much, just a few things that I need to do and I use Outlook. I have gotten so used to 2010 that I really don't want to change and I won't spend the money for 365 which is so over the top for what I need Office for. Please, any advice helps.

-- it will not validate the product key.

Where did you get the Product Key from?
Find your product key for Office 2010 - Microsoft Support

What is the specific error message when you try to register with that key?

For general Product Key problems, see
"My Office 2010 product key doesn't work" section of
Find your product key for Office 2010 - Microsoft Support