Delete Undetectable Files and Folder In WIN 7

1. Click on Start
2. Type CMD in the Search box
3. Right-click on CMD and choose Run as Administrator
4. Leave the Command Prompt window open, but proceed to close all other open programs 
5. Right click on the Task bar and click on Task Manager
6. Click on the Processes tab, click on the process named Explorer.exe and click on End Process. 
7. Minimize Task Manager but leave it open 
8. Go back to the Command Prompt window and change to the directory where the file is located. To do this, use the CD command. You can follow the example below.
   
   Example: to change to the Windows\System32 directory you would enter the following command and Press Enter
   
   cd \windows\system32
9. Now use the DEL command to delete the offending file. Type DEL <filename> where <filename> is the file you wish to delete.
   
   Example: del undeletable.exe
10. Use ALT-TAB to go back to Task Manager 
11. In Task Manager, click File, New Task and enter EXPLORER.EXE to restart the Windows shell. 
12. Close Task Manager

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