Server's Time error

[Chris]

"the server clock is not synchronized with the primary
domain controller's clock" This is the error I get when
trying to access one of my clients computer through the
network. I also get the same error when the client is
trying to log on. Any idea's? I have tried to restart
the server, and the client. I also manualy stopped and
restarted the clock through services in administrative
tools. It is only happening with this one client,
everything else is fine.

Thanks,
Chris