After changing the time zone in Win10 clock in the system tray no longer displays the correct time.

Settings applies the new time zone but the taskbar clock retains the old display until Explorer or the time service refreshes. Turn off Set time zone automatically if you intend to choose the zone manually, select the correct zone, and press Sync now under Date & time. Restart Windows Explorer from Task Manager and check whether the clock updates without restarting the PC. If not, open services.msc, confirm Windows Time is running, and restart that service once. Run w32tm /query /status in an elevated Command Prompt to verify its source and synchronization state. Check that the Region format is correct; it controls presentation but not the underlying time zone. If the problem returns after a change, test a new user. Domain-joined devices may receive time configuration through organizational policy, so collect gpresult /h report.html and ask the administrator to review applied settings before changing registry values or service startup configuration.