Creating User Profiles. 

Click Start, Settings, Control Panel. Double-click Passwords. Click the User Profiles tab. Click the Users Can Customize Their Preferences And Desktop Settings Option. Click OK and restart Windows. When Windows reboots, enter your username and password at the logon prompt and click OK. Log off and repeat for each user profile you create. You may want to create a Guest login.

Now that you have created the user profiles, you can restore the items that you wanted to appear only on your Desktop and Start Menu by logging on under your name and then moving the items. If there are items that you want to appear under any other User accounts, you would repeat this process under their login names.

If you have security software on your system, re-enable it.

Every time you are finished working, log off by clicking the Start Button, choosing Log Off, and clicking Yes. The next person who uses the computer will have to log on before he or she has access to the system.

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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