Delete An “undeletable” File
Open a Command Prompt window and leave it open.
Close all open programs.
Click Start, Run and enter TASKMGR.EXE
Go to the Processes tab and End Process on Explorer.exe.
Leave Task Manager open.
Go back to the Command Prompt window and change to the directory the AVI (or other undeletable file) is located in.
At the command prompt type DEL where is the file you wish to delete.
Go back to Task Manager, click File, New Task and enter EXPLORER.EXE to restart the GUI shell.
Close Task Manager.

Or you can try this
Open Notepad.exe
Click File>Save As..>
locate the folder where ur undeletable file is
Choose ‘All files’ from the file type box
click once on the file u wanna delete so its name appears in the ‘filename’ box
put a ” at the start and end of the filename
(the filename should have the extension of the undeletable file so it will overwrite it)
click save,
It should ask u to overwrite the existing file, choose yes and u can delete it as normal
December 14th, 2009 at 5:58 pm
Quite inspiring,
This is a great “how to”
Thanks for writing, most people don’t bother.
Keep up the good work,
May 4th, 2010 at 11:49 am
i have tried option 2 but it creates a zero kb file and its the only one that can be deleted. i did not try the first one coz taskmgr opens and closes a second after.
May 11th, 2010 at 7:11 pm
this helps