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spidey3

macrumors regular
Jul 1, 2010
195
0
Instructions for Lion:
Go to System Preferences..., and look at the Users & Groups section. Select your account, and use Change Password... button to set a password.

Then go to Security & Privacy. In the General section make sure that Require password <time> after sleep... is enabled.

Details may differ slightly for others OS X versions.

In future though, please take the time to search around for answers [google is your friend] before posting.
 
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