System Error. Code:161

Receiving the following error although the files are delivering:

<filename value="\\vsacfs28\group\Scout\ScoutOnly\Bloomberg\Bloomberg.xls" />
<destination value="/UPLOAD_SCT_FILES_BLOOMBERG/Bloomberg.xls" />
<result success="true" />
</upload>
- <touch>
<filename value="/UPLOAD_SCT_FILES_BLOOMBERG/Bloomberg.xls" />
<modification value="2014-10-24T13:19:56.000Z" />
<result success="true" />
</touch>
- <failure>
<message>Error listing directory '/\'.</message>
<message>Error retrieving file list for "/\*.*".</message>
<message>System Error. Code: 161.</message>
<message>The specified path is invalid</message>

Was using WinScp 4.2.9 recently upgraded to 5.5.6 and was not receiving this error in earlier version.

SFTP protocol

Here is my script line:
winscp.exe /console /log=%apx_root_log%\dlyBloomberg_%yyyy%%mm%%dd%.xml /command "option batch on" "option confirm off" "open UMB" "put \\vSacFs28\group\Shared\APX\Auto\Bloomberg\Output\bloomberg1.xls / /UPLOAD_SCT_FILES_BLOOMBERG/" close exit

Please attach a complete session log both from 4.2.9 and 5.5.6. Just change .xml to .log in log file name.