Problem in accessing sharepoint site

 Hi All,
I am developing a ASP.Net application  (coding in C#).
This is the problem I am facing:
According to my requirement, I have to access a sharepoint 2007 site which is on another server, but on same domain. My server is server1, but the url of the server which I have to access programmatically is http://server2/

when I try to access, it gives me the following error-
System.IO.FileNotFoundException was unhandled by user code
  Message="The Web application at http://192.168.1.157:4040 could not be found. Verify that you have typed the URL correctly. If the URL should be serving existing content, the system administrator may need to add a new request URL mapping to the intended application." 
 
Can somebody help. It's urgent.
 
Thanks,
Jaimin

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