First, make sure that the time zone and date are set correctly, make sure that "Auto Set Time" and "Auto Set Time" are turned on. If it is turned on, turn it off and restart it to force refresh; 2. Click "Sync now" in the "Date and Time" settings, and if it fails, replace the Internet time server to time.nist.gov or pool.ntp.org; 3. Restart the Windows Time service through services.msc, start and set the startup type to automatic, or execute net stop w32time and net start w32time at the administrator command prompt, and run w32tm /register reset service if necessary; 4. Check whether the firewall or network blocks NTP communication (UDP port 123), try to change the network environment or contact the IT department; 5. Run w32tm at the administrator command prompt /resync forces synchronization time, if it fails, use w32tm /query /status to view synchronization status and source; 6. If the time is still inaccurate after restart, it may be that the motherboard CMOS battery (such as CR2032) is exhausted, and the battery needs to be replaced and the time is calibrated in the BIOS. Most problems can be solved by restarting the time service or replacing the time server. If it still fails to synchronize, it may be a network or hardware problem.

If your Windows PC clock is behind and won't sync automatically, it's a common issue—but easy to fix in most cases. The problem usually comes from a misconfigured time service, internet sync failure, or incorrect time zone settings. Here's how to fix it step by step.

? 1. Check Time Zone and Date Settings

First, make sure your time zone is correct—this is often overlooked.

• Press Win I to open Settings .
• Go to Time & Language > Date & time .
• Make sure:
  • Set time zone automatically is On (or manually set it correctly if needed).
  • Set time automatically is On .

If it's already on but still wrong, turn it off , wait 10 seconds, then turn it back on to force a refresh.

? 2. Manually Sync with Internet Time Server

Windows uses time.windows.com by default, but sometimes it fails to sync.

• In Settings > Time & Language , scroll down and click "Sync now" under "Additional settings".
• If it fails, click "Sync button again, or:
  • Click "Additional date, time & regional settings" (classic Control Panel).
  • Choose "Date and Time" > "Internet Time" tab.
  • Click "Change settings" .
  • Ensure "Synchronize with an Internet time server" is checked.
  • Try changing the server to one of these more reliable ones:
    • time.nist.gov
    • pool.ntp.org
  • Click Update now , then OK .

?? If you get an error like “Unable to contact server”, it might be a firewall or network issue (see below).

? 3. Restart the Windows Time Service

The Windows Time (W32Time) service might be stuck or disabled.

• Press Win R , type services.msc , and press Enter.
• Scroll down to Windows Time .
• Right-click > Restart .
• If it's not running, right-click > Start .
• Double-click it and set Startup type to Automatic .

You can also do this via Command Prompt (as Admin):

 net stop w32time
net start w32time

For a deeper reset (optional):

 w32tm /register

Then restart the service again.

? 4. Check Firewall & Network Issues

Sometimes firewalls or network policies block NTP (port 123 UDP).

• Make sure your firewall isn't blocking outbound UDP traffic on port 123 .
• Try switching to a different network (eg, phone hotspot) to rule out local network restrictions.
• Corporate networks sometimes override time servers—check with IT if on a work device.

? 5. Use Command Line to Force Sync

Open Command Prompt as Administrator and run:

 w32tm /resync

You should see:

"The command was completed successfully."

If it says “The computer did not resync because no time data was available,” then:

• The time service isn't working.
• Or you have no internet access.
• Or NTP is blocked.

You can also query the current status:

 w32tm /query /status

Look for the Last Successful Sync Time and Source .

? 6. Hardware Clock (CMOS Battery) – Last Resort

If the clock is consistently wrong after reboot , even when synched, the CMOS battery on your motherboard might be dead.

• This tiny battery (usually CR2032) keeps the BIOS clock running when the PC is off.
• If it's dead, the clock resets or drifts every time you power off.
• Replace the battery (easy on desktops, a bit harder on some laptops).

After replacing, enter BIOS and set the correct time.

Summary Checklist

• [ ] Time zone correct?
• [ ] "Set time automatically" turned on?
• [ ] Tried syncing with time.nist.gov ?
• [ ] Restarted Windows Time service?
• [ ] Ran w32tm /resync in Admin CMD?
• [ ] CMOS battery may dead?

Most cases are fixed by restarting the Windows Time service or switching to a better time server. If it still won't sync, the issue is likely network-related or hardware-based.

Basically, start simple and work up—usually it's just a glitch in the sync process.

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