Firewall blocks windows clock updating
People have reported that although they have manually set the date/time on their computer, this gets changed by the windows time server (time.windows.com) when connected to the Internet and for some reason it doesn't display the right date/time.
First off, check there aren't any releases at Microsoft's Windows Update Now below are the notes I've had to try and fix this before (personally it was because Microsoft released an optional windows update that fixed my issue.
The best thing Microsoft ever did for security was turn on the firewall by default way back in the days of Windows XP, Service Pack (SP) 2.
A firewall is a program that restricts access to (and from) your computer.
Before XP SP2, the Windows firewall was turned off by default, meaning users had to know it was there, and turn it on themselves, or be left unprotected.Windows Firewall is the default software firewall of the Windows operating system.It is enabled automatically after installation unless another firewall has been installed already and taken over.See the manufacturer’s instructions if you have a 3rd party firewall installed.Note: You should not need to modify the firewall settings on your Virtual Time Clock client computers.