Do yourself a favour if you do a fresh install after doing a upgrade to Win10. Find the Win10 Key you have on the upgraded computer and make a note of it.
I made the mistake of not having it and when it came to put in the key, the only one I had was my Win7 key which wouldn't work.
I got it installed without a key and then had to do a live chat with some Microsoft person who did a remote connection and after about 30 minutes finally activated Win10 and gave me the key for future.
I made the mistake of not having it and when it came to put in the key, the only one I had was my Win7 key which wouldn't work.
I got it installed without a key and then had to do a live chat with some Microsoft person who did a remote connection and after about 30 minutes finally activated Win10 and gave me the key for future.