I have some problem after login about " Operation failed "

[joezine]

Additional condition

Unable initialize admin session:
---------------------- Debug Info -------------------------------
0: C:\Program Files\SWsoft\Plesk\admin\plib\cmd_loginup.php:177
createSessionCommon(integer '1', string 'admin', boolean true, boolean false)
1: C:\Program Files\SWsoft\Plesk\admin\plib\cmd_loginup.php:236
createSessionAdmin(string 'admin', string '*****', boolean false)
2: C:\Program Files\SWsoft\Plesk\admin\plib\cmd_loginup.php:122
createSession(string 'admin', string '*****')
3: C:\Program Files\SWsoft\Plesk\admin\htdocs\login_up.php3:16

How can I solve this problem? I use Win 2003 and MS SQL