After applying TRA 5.9.1 hotfix 04, BusinessWorks Plug-in for sFTP throws NullPointerException while the same project used to work fine. 
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Time : 2017-02-03T04:07:07.581-05:00 Operation : Processing Single File Status : ERROR Message : Error processing source file: /AD-SVA3BE13/20170116104602-novdecline10.csv to the target destination with target file name: /apps/eip_share/it/77/application/landing_zone/marketing/dnxbatch/20170116104602-novdecline10.csv   Error: <?xml version="1.0" encoding="UTF-8"?>
<ns0:Output xmlns:ns0="http://www.allstate.com/ets/tibco/schemas/ErrorOutput"><ns0:ErrorCategory>SYSTEM_ERROR</ns0:ErrorCategory><ns0:ErrorReport><ns0:StackTrace>Job-32513214 Error in [BusinessProcesses/FTPService/SubProcesses/GetFileByReference.process/Group/FTPS-Binary-PAS]
java.lang.NullPointerException
    at java.lang.StringBuffer.&lt;init&gt;(Unknown Source)
    at com.tibco.plugin.ftp.FTPControlSocket.a(Unknown Source)
    at com.tibco.plugin.ftp.FTPControlSocket.if(Unknown Source)
    at com.tibco.plugin.ftp.FTPClient.quit(Unknown Source)
    at com.tibco.plugin.ftp.FTPTransport.closeConnection(Unknown Source)
    at com.tibco.plugin.ftp.FTPGetActivity.eval(Unknown Source)
    at com.tibco.pe.plugin.Activity.eval(Unknown Source)
    at com.tibco.pe.core.TaskImpl.eval(Unknown Source)
    at com.tibco.pe.core.Job.a(Unknown Source)
    at com.tibco.pe.core.Job.k(Unknown Source)
    at com.tibco.pe.core.JobDispatcher$JobCourier.a(Unknown Source)
    at com.tibco.pe.core.JobDispatcher$JobCourier.run(Unknown Source)
</ns0:StackTrace><ns0:Msg>Job-32513214 Error in [BusinessProcesses/FTPService/SubProcesses/GetFileByReference.process/Group/FTPS-Binary-PAS]</ns0:Msg><ns0:FullClass>java.lang.NullPointerException</ns0:FullClass><ns0:Class>NullPointerException</ns0:Class><ns0:ProcessStack>BusinessProcesses/FileTransportService/StarterProcesses_LB2/FTSManifest_LB2.process/Group (1)/Group/Iterate to FTP all files/ProcessFile&gt;BusinessProcesses/FileTransportService/SubProcesses/ProcessFTSInput.process/Group/ProcessSingleFile&gt;BusinessProcesses/FileTransportService/SubProcesses/ProcessSingleFile.process/Group/GetFile&gt;BusinessProcesses/FileTransportService/SubProcesses/GetFile.process/FTP Get&gt;BusinessProcesses/FileTransportService/SubProcesses/InvokeFTPGetService.process/Repeat On System Error/Invoke FTPService&gt;BusinessProcesses/FTPService/SubProcesses/FTPService.process/GetFile&gt;BusinessProcesses/FTPService/SubProcesses/GetFile.process/Get File Activity Group/Get File By Reference&gt;BusinessProcesses/FTPService/SubProcesses/GetFileByReference.process/Group/FTPS-Binary-PAS</ns0:ProcessStack><ns0:Data/></ns0:ErrorReport></ns0:Output> 
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