hello, whenever i try to open mycomputer or some folder or even ctrl panel... i get this error saying ' data execution prevention' ......to help protect your computer, Windows has closed this program. could someone plz help me thanking you in advance.

If a program is failing and you want to disable DEP to see if that is the cause. Here are the steps. (Just disable DEP for the program in question... don't disable it for your whole system.) 1. Click Start 2. Select Control Panel 3. Select System 4. Click the Advanced tab 5. In the Performance region select Settings 6. Click the Data Execute tab in the dialog box that opens 7. Select Turn on DEP for all programs and services except for those I select 8. Click Add. 9. The open dialog box will open. Browse and select your application. 10. Click Open 11. Click Apply 12. Click Ok 13. Reboot in your case i suspect c:\windows\explorer.exe if that doesn't help, turn off DEP altogether and scan your system for malware.