The command line utility that helps you change the time zone in Windows 7 is tzutil.exe and is known as Windows Time Zone Utility. This is a great tool for all the people who prefer working from the command prompt.
Use the /s parameter to set the time zone:
tzutil /s "universal standard time"
Use the /g parameter to get the time zone:
tzutil /g
Use the /l parameter to list the valid time zones.
tzutil /l
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