Hi Ammar,
After setting up worker directory on CAD worker, you will also need to configure CAD worker agent from CAD worker administration. If you already did this, then please hare you agent.ini file.
Also check if you have following property set in wvs.properties
<Property name="worker.exe.whitelist.prefixes" overridable="true"
targetFile="codebase/WEB-INF/conf/wvs.properties"
value="C:\|D:\|G:\|/|nohup /"/>