Remote server error 500 internal server error in client object model

 Hi,

I am copying the Document Library files from one sharepoint server to other sharepoint server library using Client object model. I have also added the server login credential in my code.

Even though  I am getting the "Remote server error 500 internal server " error  at below code.

SP.File.SaveBinaryDirect(oTargetClientContext, nLocation, fileInfo.Stream, true);

any idea why i am getting this error ???

Thnx