I have a windows machine that keeps giving me a message to "activate windows". I did this once, and it worked for a day. But now it's asking me again. I'm using the key that came with the machine to do this. I really don't want to spend 200.00 to buy another key. Plus doing this will force me to set up my computer again. Not really a big deal, but time consuming. Any suggestions would be helpful. It's running windows 10.thanks. I should state that other than this message, the computer is operating just fine.