Windows time not syncing? How to fix the clock in Windows 11 and 10

Fix 1: Sync from Settings

1. Right-click the clock on the taskbar and choose Adjust date and time, or go to Settings > Time & language > Date & time.
2. Turn on Set time automatically. Turn on Set time zone automatically too, or pick the right zone in the Time zone list. A wrong time zone gives a clock that is off by whole hours even though it is syncing correctly.
3. Select Sync now. On Windows 11 it’s under Additional settings; on Windows 10 it’s in the Synchronize your clock section. The page then shows the last successful sync and the time server used.

If Sync now shows an error such as Time synchronization failed, carry on with the fixes below.

Fix 2: Set the time by hand if it’s far off

This is the cause most guides miss. Microsoft documents that on a PC that isn’t in a domain, the Windows Time service won’t correct the clock by more than 54,000 seconds (15 hours) in either direction. If the clock is further out, for example after a dead battery reset it to an old date, the service logs an event and leaves the time alone, so syncing seems to do nothing.

Turn off Set time automatically, select Change next to Set the date and time and enter the correct date and time. Then turn Set time automatically back on and select Sync now. Once the clock is close, syncing keeps it accurate.

Fix 3: Start the Windows Time service and resync

Settings relies on the Windows Time service (w32time). Open Command Prompt as administrator and run:

net start w32time
w32tm /resync

If the service is already running, the first command just says so. To see where the PC gets its time and when it last synced, run:

w32tm /query /status
w32tm /query /source

Don’t worry if services.msc shows Windows Time as Manual (Trigger Start) and stopped. Microsoft says that’s the default on PCs that aren’t in a domain: the service starts when it’s needed and then stops again. A scheduled task called Synchronize Time (Task Scheduler Library > Microsoft > Windows > Time Synchronization) handles the regular syncs. If that task is disabled, automatic syncing won’t happen.

What the w32tm errors mean

Message	What it means	What to do
The computer did not resync because no time data was available.	The PC sent a time request but got no valid reply	Fix 4, then Fix 5
The service has not been started.	Windows Time isn’t running	net start w32time, then resync
Sync appears to work but the time doesn’t change	The clock is more than 15 hours out	Fix 2
The clock is off by an exact number of hours	Wrong time zone	Fix 1, step 2

Microsoft lists three causes for the no-time-data error: the server name can’t be resolved (a DNS problem or a typo in the server name), UDP port 123 is blocked by a firewall, or the server you chose isn’t actually an NTP time server.

Fix 4: Reset the time server settings

If someone changed the time server or the settings are corrupt, point Windows back at Microsoft’s default server, time.windows.com. In the admin Command Prompt run:

w32tm /config /manualpeerlist:"time.windows.com,0x9" /syncfromflags:manual /update
w32tm /resync /rediscover

/update applies the change immediately, and /rediscover makes Windows look up the server again before syncing. Some guides add /reliable:yes; Microsoft says that setting only matters on domain controllers, so leave it out on a home PC.

If that still fails, many users reset the service to its defaults with the commands below. /unregister removes all Windows Time settings and /register adds the defaults back, so any custom server you set will be lost:

net stop w32time
w32tm /unregister
w32tm /register
net start w32time
w32tm /resync

If /register reports an error, restart the PC and run the last three commands again.

Fix 5: Check DNS and the firewall

Time sync uses the NTP protocol on UDP port 123. To test whether the PC can reach the server at all, run:

w32tm /stripchart /computer:time.windows.com /dataonly /samples:5

Lines with a time offset mean NTP gets through. Errors on every sample mean something is blocking it. Check these in turn:

• DNS: if nslookup time.windows.com fails, the PC can’t resolve the server name. Fix your internet connection or DNS first.
• Third-party firewall or security suite: allow outgoing UDP traffic to port 123. If you’ve created your own outbound rules in Windows Firewall, see how Windows Firewall rules work and make sure none of them blocks it.
• VPN or restricted network: some VPNs and public or office networks block NTP. Disconnect the VPN and try Sync now again.

A wrong clock causes other problems too, such as certificate errors in browsers and update failures like We couldn’t connect to the update service, so fix the time first.

If the clock is wrong after every restart

If the time is right after syncing but wrong again every time the PC has been switched off or unplugged, the hardware clock isn’t keeping time. On desktops the usual suspect is the small coin battery on the motherboard (often a CR2032), which keeps the clock running while the PC is off. Replacing it is cheap, but check your PC maker’s instructions first. Laptops may need a service visit.

Dual-booting with Linux is another common cause: Linux usually stores the hardware clock in UTC while Windows expects local time, so each system shifts the clock when you switch. The usual fix is to tell Linux to use local time; Microsoft doesn’t document a Windows-side setting for this, so be cautious with registry tweaks you find online.

Work or school PCs

PCs joined to an Active Directory domain get their time from the domain, not from time.windows.com. Microsoft notes that Group Policy settings overwrite local Windows Time settings, so changing the server yourself won’t stick. If a work PC’s clock is wrong, tell IT. They can return it to domain time with w32tm /config /syncfromflags:domhier /update followed by restarting the service.

Related guides

• How to open Command Prompt as administrator in Windows 11 and 10
• How to block a program in Windows Firewall (Windows 11 and 10)
• “We Couldn’t Connect to the Update Service”: 7 Fixes for Windows 11/10

Official sources:

• Microsoft Learn: Windows Time service tools and settings
• Microsoft Learn: w32tm /resync fails because no time data was available
• Microsoft Learn: Windows Time service doesn’t start automatically on a workgroup computer