If time synchronization fails

When you click the Update Now button, your clock should be synchronized immediately. If it fails, it might be for one of the following reasons:

• You are not connected to the Internet. Establish an Internet connection before you attempt to synchronize your clock.
• Your personal or network firewall prevents clock synchronization. Most corporate and organizational firewalls will block time synchronization, as do some personal firewalls. Home users should read the firewall documentation for information about unblocking network time protocol (NTP). You should be able to synchronize your clock if you switch to Windows Firewall.
• The Internet time server is too busy or is temporarily unavailable. If this is the case, try synchronizing your clock later, or update it manually by double-clicking the clock on the taskbar. You can also try using a different time server.
• The time shown on your computer is too different from the current time on the Internet time server. Internet time servers might not synchronize your clock if your computer's time is off by more than 15 hours. To synchronize the time properly, ensure that the date and time settings are set close to your current time in the Date and Time Properties in Control Panel.