CTS Configuration error in BODS 4.2

Hi Experts,

I am configuring CTS for BODS system by following the below document. while exporting objects i am facing the error as

{14.2) 08-23-16 10:30:13 CTSExportTransport: Clean .zip files in directory null/workspace/cts_export

(14.2) 08-23-16 10:30:13 (E) Caught exception : No such file or directory}.

Configuration Guide for CTS+

I am not sure where do i need to maintain the directory,So can you please help me in resolving the issue.

Thanks & Regards

Teja