That's a setting in your AD . Let's open your MMC ( global or by OU .. depend of where you want to applicate it )
By default, Windows will notify users 14 days before their password expires. You can change the 14 day value and increase or decrease it, depending on your requirements. This can easily be accomplished by editing the appropriate GPO or the local computer policy. You can change the default value in Windows XP using the steps below:
I set the default domain policy that is linked to an OU to warn users 7 days before the password is going to expire. It still warns at 14 days.
I changed this setting:
Click Start and click Run.
Type gpedit.msc and click OK.
Expand the following: Computer Configuration | Windows Settings | Local Policies | Security Options.
In the right pane, double click Interactive logon: Prompt user to change password before expiration.
Am I missing something here? Is this the correct place to change it. This is a Windows 2003 native domain. Clients are XP and it occurs for all clients.