directly from your help & support window.
search for word time
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To change the way your computer displays the time
Open Regional and Language Options in Control Panel.
On the Regional Options tab, under Standards and formats,
click Customize.
On the Time tab, specify any changes you want to make.
If you do not see the format you want in Time format,
follow these guidelines:
To Do this
Display time in a 24-hour format
Type uppercase H or HH for the hour
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