IIRC windows doesn't run ntp by default, it runs some propretary w32time service instead. I think it has an ntp client built in, but I'm not sure if it can be an NTP server out of the box.

Incorrect time on a Windows device or server can prevent security updates or user authentication, and it can interfere with a forensics investigation. The recent U.S. daylight saving time change ...

A mysterious issue is affecting the default Windows NTP server (time.windows.com), according to multiple complaints coming from Reddit and Twitter users, screwing up everyone's computer clocks. Based ...

Most Hackaday readers will be familiar with the idea of a network time server; a magical box nestled away in some distant data center that runs the Network Time Protocol (NTP) and allows us to ...