10/1/2017 8:47:15 AM: [3] Error while uploading mails for ::654229960

10/1/2017 8:47:15 AM: [3] The underlying connection was closed: An unexpected error occurred on a send.

10/1/2017 8:47:15 AM: [3]    at ZohoUserMigration.ZohoMailUploadHandler.uploadTable(String userDataHomePath, ZohoMailMailBoxInfo mailboxInfo, ZohoMailPstInfo pstinfo)

   at ZohoUserMigration.ZohoMailUploadHandler.startPstUpload(String zuid, ZohoMailPstInfo pstInfo, BackgroundWorker bgWorkerRef, ZohoMailMailBoxInfo myMailboxInfo)