Change the time zone in Windows 7

To change the time zone that is specific to your region, perform the following steps:
1. From the taskbar, right-click on the clock and then click on Adjust Date/Time.
2. Click on Change date and time settings... (If you are prompted for an administrator password or confirmation, type the password or provide confirmation).
3. From the Date and Time dialog box that opens, under Time zone section, click on the Change time zone... button.
4. From the Time Zone Settings dialog box that opens, click on the Time zone: drop-down box and select your time zone.
5. For the daylight saving time to take effect automatically, click to place a check mark beside Automatically adjust clock for Daylight Saving Time.
6. Click OK to close Time Zone Settings dialog box.
7. Click OK again to close Date and Time dialog box.