Help Regarding Email Problem

[Asstt. Mgr. Systems STL]

Hi all freinds,

I am using a Linux based server for Email with following specs:
 
OS:- Linux 2.4.7-10 i686 unknown 
PERL /usr/bin/suidperl 5.006
WebMail:- southerntravels.net 

PROTOCOL
SERVER_PROTOCOL HTTP/1.1
HTTP_CONNECTION Keep-Alive

SERVER
HTTP_HOST 192.168.0.1:800
SERVER_NAME southerntravels.net
SERVER_SOFTWARE Apache/1.3.19 (Unix)

I have 2 e-mail accounts namely "user1" and "user2" both having same passwords and same settings.

When I access "user1" account through Microsoft Outlook Express, it shows connected to the server but ask for correct password. I have entered a lot of time the correct password but account was not accessed.

Then I do the same process with "user2" and it was done successfuly.

Then I delete "user1" from Server, and shut it down for 10 minutes.

Then after restarting I made an account "user1" with same password and settings as of "user2". Then again I tried to access it through Microsoft Outlook Express on a different client machine but it is not accessed.

I have reset password several times on server even then it is not accessible.

There is a note able thing, i.e, "user1" is accessible through web mail. but inaccessible in Outlook Express or Incredi mail.

Can Any One help me in solving this problem?
Any TIP, solution, Trick, Suggession or helping link regarding this will be warmly welcomed.

Best Regards

Umar Shabbir,
Deputy Manager Systems,
Southern Travels (pvt) Ltd.