An apparent technical issue with a Microsoft server is leading to a number of users and data centers running Windows to receive the wrong time and date.

The issue appears to stem from a network time protocol (NTP) server hosted by Microsoft at time.windows.com. According to users who are experiencing the problems, their systems are off by an hour and are occasionally displaying times that are entirely nonsensical.

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Reports first starting circulating on Reddit and Twitter, where users began talking about the issue. Most noted their clocks were off by about an hour, while some reported seeing odd time jumps or minutes with 61 seconds.

“It's 10:53... then 10:20... then 10:35…” one affected user wrote on Reddit.

Reports have carried on since early Monday morning and appear to have persisted throughout the day. It’s unclear what exactly is the cause of the issue, though speculation has grown as Microsoft has remained silent regarding the problem.

One explanation that has gained traction online as users scramble for answers is the suggestion that a cluster of time servers may have lost connection with an external source that syncs the time and date.

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Producing the wrong time can cause a considerable amount of problems for users, as it produces incorrect timestamps for every event and action on the system and can cause timed actions to be performed at the wrong time.

According to the Internet Engineering Task Force’s Network Time Protocol Best Practices, network security mechanisms often rely on time as part of their operation. “The best way to protect computers and networks against undefined behavior and security threats related to time is to keep their NTP implementations current,” the framework says.

“We investigated and quickly resolved the issue our time service experienced,” a Microsoft spokesperson told International Business Times.

How To Change Your NTP Server

To check and see if your machine has been affected by the issue, you can ping the Windows Time Service servers to see check the clock strata. If the server returns “straum 16,” then odds are your device is unsynchronized.

If your computer or network has been hit by the time mix up, you can switch to an alternative NTP until Microsoft gets its server synced back up. There are a number of options out there, including NIST, NTP and Google —just check the compatibility with your system before making the change.