How can I close a file that is open in another program ?

Iwant to delete a file. I am logged on as Administrator, have taken ownership, have Effective Permission to perform a deletion, but I am unable to delete a file because it is being used by another program.

I performed a Safe Mode boot; tried to delete it and still it was being used by another program.

The file name is shellext.dll. It's location is C:/Programs & Files/ Microsoft Security Client.
How can find out what program has opened it and close it?

KC

I seems that the file is part of MSE antivirus and the file is the shell extension that provides shortcuts inside Windows Explorer. Why you want to delete that?
Even if you manage to do so, having a missing file might cripple MSE or create problems with Windows explorer.

Alejandro85 said:

Why you want to delete that?

I uninstalled MSE, this file was left behind.

KC

Layback Bear - I followed the link you provided called What is it? One suggestion was to use a bat file to delete shellext.dll before it is used by another program.

What should be in a bat file used to delete shellext.dll? Would it be like this?
File name: Good_By_shellext.bat
Line 1: delete C:/Program Files/Microsoft Seurity Client/shellext.dll
Line 2: exit

How can a bat file be put into Windows 7 start-up?

KC

Have you rebooted after uninstalling MSE? If so, are you still seeing the context menu options from MSE in Explorer?

You may have to look in the registry then and delete from there so the file doesn't gets loaded then and you'll be able to delete it thereafter.

gigagiggles said:

Find, download and run as administrator, Autoruns. If the .dll is in the list, untick, and see if the .dll can be deleted.

Autoruns worked, shellext.dll has been removed from the drive.

KCav, great news to read. I do think the Forum would like you to mark this thread as solved for easy identifiability. Thank you!