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I have Ubuntu 10.04 installed on my system. Recently, I was swapping out hard drives and, when I rebooted my system, I could not log in. I would enter my username and password; then the system would return immediately to the login screen and prompted the error message:

Module is Unknown.

I found that I was missing seven pam_*.so files from /lib/security (although I do not know why). It happened immediately after I removed a secondary drive.

  • Can I simply reload the missing files manually?
  • Is there something that I did to cause the files to disappear (strong word, disappear!)?
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If you use an Ubuntu CD, you can run it in live mode. Then you may be able to copy the files over manually using the cp command. If you can't do it that way, (since to be honest, I don't know where they would be on the CD) you can get the files off of another computer running ubuntu and copy them to a flash drive and copy them that way.

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Thank you. Do you know of any reason for the files to be deleted? – user76063 Jul 9 '12 at 22:27
No, I don't. I'm still new to Ubuntu myself. If my comment was useful, please don't hesitate to click the up arrow saying it was useful. – Corey Whitaker Jul 9 '12 at 22:40

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