I m not using any code to run the webservice. I used data connection wizard to connect to webservice. I can retrieve the value offline. but when i try publish it in the sharepoint site it throws an error 5566 and says Continue or start over. if i give continue the username textfield for which the webservice is used is shown blank.
later i figured out that when i have mutliple browser open at the same time in sharepoint with different user login, then the problem arises.
But i need to figure for a work around in using such webservice.