Unable to change security settings in workgroup computer

I have a Windows XP Pro machine that was originally part of a domain.
Domain policy enforces minimum password length, password changing
every 90 days, etc. I've removed the machine from the domain, but I'm
still unable to change these settings. I run gpedit.msc, and navigate
to Local Computer Policy, Computer Configuration, Windows Settings,
Security Settings, Account Policies, Password Policies. Here I see
the options I'd like to change, but when I open the properties for
each item, the value is greyed out.

Is this by design? Do I have to wipe the machine and start over to
enable changes to these settings?

Thanks for any help,
Gary

When you try to make these changes, I assume you are
logged on as a Local Administrator yer?

Regards

Mike Bright MCP, MSP

e:mike.bright@brightweb.co.uk