The underlying connection was closed: An unexpected error occurred on a receive

 Hi,
 
i have developed a webservice in .NET 2.0., from my webservice i am calling a webservice of client which is also in .NET2.0(it's on SSL). but last few days i am getting an error "The underlying connection was closed: An unexpected error occurred on a receive" whenever i am calling a webmethod. i am calling 4 methods of client webservice by creating object of that webservice, first three webmethods works fine but when i call 4th web method i receive above mention error. can anyone suggest solution for this. i searched on google i got one site which explain about proxy but i am not knowing proxy settings of my server. also i want to know this problem is from my server or client's server. 

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