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Date: Thu, 20 Feb 1997 14:07:20 -0600 (CST)
From: Mark Tinguely <tinguely@plains.nodak.edu>
Message-Id: <199702202007.OAA04028@plains.nodak.edu>
To: ouyang@us.ibm.com, questions@freebsd.org
Subject: Re: xdm
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>  I got the login screen as it was supposed to. However, after I
>  entered the username and password, the system returned to the
>  login screen again. I tried to reboot the system but got the
>  same result. Would you please tell me how can I fix this problem?

log into your account from another account (or type Alt-Ctrl-F2 to
use a virtual console) and check your .xsession-errors file for messages.
My guess is that you are:

1) missing an .xsession file with commands for xdm to use
2) the .xsession file is not executable
3) the commands in the .xsession script are all specified to be run in the
   background and this completion of the .xsession script causes xdm to go
   back to the login screen.
4) some other serious like incorrect PATH to a command in the .xsession file

--mark.