Thanks, it appears that installing WinXP from an installation CD only lasts 30 days as the license number authentication process is said not to be online any more.
There is some more about installing Windows XP Mode here
https://www.tomshardware.com/uk/revi...mments-1182492 I hope WinXP Mode does not have a 30 day limit.
The only reason I wanted to instal winXP was to play its "Internet Reversi" game, but I have just found out that it is unlikely to be available:
https://answers.microsoft.com/en-us/...5-37f6355fec39 They did announce its ending some years ago, but despite their earlier announcement it was still functioning and playable. What appears to be a second announcement is probably really the end.
I have tried every available Reversi/Othello game, but there is nothing as good as playing online against a real human.
Update:
https://www.playok.com/ allows online playing of games against other humans, without registration.