I am trying to install some software and it requires removing the following file:

  • cd %SYSTEMROOT%\assembly\GAC
  • rename Microsoft.Office.Interop.Outlook Microsoft.Office.Interop.Outlook.Old

the problem is that when I do the rename, it looks like it's successful but it doesn't seem to actually delete Microsoft.Office.Interop.Outlook

i tried to explicitly do:

 del Microsoft.Office.Interop.Outlook 

and again it looks like it works but then when i do a "dir" i still see that file.

Do you have any suggestions on why this wouldn't allow me to delete this file. I have outlook closed when i am doing this so i wouldn't think outlook is locking the file.


1) you could use sysinternals ProcessMon to see what's using the file. Kill that, then delete the file.

2) You could also use the RunOnceEx registry key to have the file deleted on boot before you run anything that may use it. I don't have a windows box to create an example, maybe someone else can add to this answer.


Boot from a XP cd and get to the command prompt, delete it from there.

here is how to get to the command prompt from CD.



When this happens to me I use Unlocker by Cedrick Collomb.

This little and hand utility always did the trick for me really easily: right click --> unlock & delete.


It is easier and more feature-packed than other suggested tools (check the "Similar programs and why Unlocker is better" table in the link above)

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