WIn XP

[Kartick]

After Installing Anti-Virus a scan was done.Win XP logs in
and logs out immediately. Tried in Safe mode same thing.
It goes in till applying settings and logs off
immediately.Tried Last Known good config too no use. Tried
through Recovery Console too. Nothing Works

 

[Jupiter Jones [MVP]]

Perform a Repair Installation:
http://www.dougknox.com/xp/tips/xp_repair_install.htm
Windows Updates will need to be reinstalled.
Data should be safe, back-up important data just in case.
Install Service Pack first and by itself.
Then install ALL Critical Updates no more than 4 at a time,

Disconnect the network/modem cable before starting repair and do NOT
reconnect the cable until repair is completed and firewall is
installed/enabled.
http://support.microsoft.com/?kbid=283673