error while loging in plesk panel

[balechaparka]

When i try to login to my plesk panel i am getting folllowing error.
ERROR: Exception
The system cannot find the file specified. (Error code 2) at Unable to connect to pipe \\.\pipe\P_8c0c0f6a-2b6c-49b6-a025-efc6eed9700d

0: constants.php3:62
get_admin_password()
1: constants.php3:62
require_once(string 'C:\Program Files (x86)\Parallels\Plesk\admin\plib\constants.php3')
2: auth.php3:89

I have not changed any files, still why this error comes? How can i solve it? It's urgent i am not able to login.
Plesk version:11.0.9 and OS is Microsoft Windows Server 2008 R2 Service Pack 1.

 

[IgorG]

http://kb.parallels.com/en/112826

 

[balechaparka]

I followed that article but it didnt help me. I am still getting same error.

 

[balechaparka]

I am still facing same problem.Not able to login. Can anyone help me please..