hi i am getting proble, with my smf, i am not able to login my admin area it always say incorrect password althogh pass word is right i tried clearing out cookies but no help, soem time i logged in but some time not its random problem my forum is studentlife.co.in/forum
What's your smf version? What kind of sessions are you using under Server > Cookies and Sessions? You might want to try specifying a non-default cookie name just to make sure the cookie of same name you received from another smf forum isn't interfering. I can't load your site so I can't provide even a general tip other than the above. Your best bet would be to go to Simple Machines Official Forum http://www.simplemachines.org/community/index.php and post in the appropriate smf version thread and ask for support there.
Alright, I can load your site now. What does the error logs show you around that instance of failed login? Admin > Error Logs It will most likely be under Critical Errors or just combined under "user". And how many times does it require for you to successfully login? Very rare but sometimes I have to log in 2-3 times to get in.
This to me sounds like a browser problem; I'd make sure it is accepting the cookies. SMF has a wonderful support forum; if you haven't got this sorted out yet I would join it and ask over there.