Unable to copy a file from one server to another

Hi All,
   I am using file upload to browse a file on a remote server(srcServerName) on click of the button (bntUpload) i am copying the file to another server (destServerName).It's a ASP.NET application with VB.NET as code behind.

Private Sub btnUploadFile_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnUploadFile.Click
 Dim srcFilePath As String = "\\srcServerName\srctemp\srcfilename.TXT"
 Dim destFilePathAs String = "\\destServerName\desttemp\srcfilename.TXT"
 Try
    File.Copy(srcFilePath, destFilePath, True)
 Catch ex As Exception
    UtilityTier.ApplicationError.ReportError("SIInitAndEduInterface-btnUploadFile", ex.Message)
 End Try
End Sub
Exception Message:- Access to the path '\\destServerName\desttemp\srcfilename.TXT' is denied.
srcServerName, destServerName are runn ...