increasing time out

Increasing the time out would solve the application problem but it would create a bigger user problem. Expect the user to be impatient, especially if they are on a high speed data connection and are used to getting fast page loads. Your application taking a while to return and then timing out is going to look like your application failed or is just not responding. This is going to frustrate your users. My best suggestion is to let them know it is a possible lengthy proccess and to check back in an expected amount of time. That is assuming you cannot use a timer to auto refresh the page. If it generally takes a minute tell the user to check back in a minute or two.

u got my problem partially. i'm using C++ application written in unmanaged C++(VC++) on .net. I add web reference to my service. then, it creates proxy class for that. i uses that class object for accessing web methods. then experience the describe problem. I observed one thing, when i uses C# application and add web reference of my service, then i can set 'timeout' property of proxy class. there is nothing like this, in unmanaged code

If I am understanding what you are attempting to do here then the behavior you are experiencing is normal and needs to be handled another way. Almost every browser has a timeout so that the user does not sit there forever staring at a page that is not responding. Even if they did not, the user would most likely move on out of impatients. The fact that your service is taking longer than the browser and user can wait cannot be helped. The best you can do is notify the user of the lengthy process and if you can auto refresh the page through a javascript timer or HTML header redirection. You could use a java script timer to submit a post so that the page reloads. On the page load check to see if the process has finished. Did I misunderstand what you were asking for?