Password-Protect Your Computer While It Is Asleep

9. From the Start menu, go to Settings, then Control Panel. 
10. Double-click on Power Management. 
11. Click on the Advanced tab. 
12. Click to put a dot in the box that says Prompt for Password. 
13. Click OK. Now when your computer comes out of hibernation, you will be prompted to supply the password that is listed in Password Properties. 
You can change your password by going to the Start menu, Control Panel, then Passwords. 

Access Manager - More info

     If the above options do not provide enough security for you, download Access manager for Windows.

Access manager provides much more security than standard ways in Windows.

More info

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