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I ran net use on the P: drive then later switched back to drive C: and issued net use p: /d.

Now the P: drive letter is no longer available to the net use command. When I try to issue another net use command I receive:

System error 85 has occurred.
The local device name is already in use

When I type p: Enter, I receive: Logon failure: unknown user name or bad password

When I type net use p: /d again, I receive: The network connection could not be found

How can I clear this phantom drive?

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up vote 0 down vote accepted

So it turns out there's nothing weird about net use and Windows7.

I had another (custom) application that was using net use in the background and it still had the drive mapped. Why I was getting the Logon Failure message, though, just by typing p: Enter is beyond me.

After finding and uninstalling that app, problem solved.

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