I have a XP machine which was part of the domain, I removed the machine from the domain but it still keeps the group policies. I cannot alter or change or even remove the logon message after pressing Ctrl/ALT Del.
Can some one please assist on this.

Thanks

Why don't you go to the domain or system administrator to remove the group/domain policy from your PC?

It's a laptop, from the old office. Don't work there anymore. So that know it can work. Is threre no where in the registry where I can do that. Special the message

Try logging in with an Admin account and switching the computer to a Workgroup.

I have already remove it from the domain to the Workgroup. But the domain group policies still applies. Did that before and it worked fine. It's the first time to see this

If you want to register this looks like the exact problem you are having:
Windows XP Operating System: Remove Group Policy from machine no longer on domain