"Password Will Expire Soon" Message When You Unlock Your Windows Vista PC
An error message informing you that your password will expire soon and asking you to change it may be displayed, when you unlock your Windows Vista computer on which you are logged on through cached credentials.
You may need to log on locally to your Windows Vista computer using cached credentials, if the domain controller is not available at the time of log on. If in this condition, you lock your computer, then when you unlock it, the warning message described earlier may be displayed. However, as your user account is actually created on the domain controller, you may not be able to change the password until the domain controller is available again. This is the reason why, you will be able to change the password only when you log on to network the next time, when the domain controller is functional.
The warning message may also display, if you change the password to your user account from another computer connected to the same network. In this case, your cached credentials will not reflect the new password until you log on to the network again and the error will display when you unlock your locked Windows Vista computer. To resolve the problem and update the cached credentials, log out and log on again to the Windows Vista computer using the new password.
windowshelp.net