Windows only: If you have a computer that multiple people access and you'd like to keep them from accessing a certain drive on your computer, a simple edit in the Local Group Policy Editor can make that happen.
If you're running Windows 2000 and above — unfortunately excluding Windows Vista and Windows 7 home editions — you can easily restrict access to local drives by changing a flag in the Local Group Policy Editor, which is launched by typing gpedit.msc in the run box, and selecting which drives you would like to restrict. Over at How-To Geek they explain:
Now navigate to User Configuration Administrative Templates Windows Components Windows Explorer. Then on the right side under Setting, double click on Prevent access to drives from My Computer.
From there you can access the drive restriction options seen in the screenshot above and select which drives you would like to restrict. For a screen by screen walkthrough and additional tips, check out the full guide at How-To Geek. Have another trick or tip for security Windows using built-in tools? Let's hear about it in the comments below.
How To Restrict Access To Drives In My Computer In Windows [via How-To Geek]