I have already added a custom domain www.poorvididi.org to my site poorvididi.vndv.com. But now its not working.

Also when I tried to goto Add Custom Domain link its not showing my domain there. If I add the same domain again it gives error Fatal error: Failed to symlink('/www/vndv.com/p/o/o/poorvididi/', '/www/org/p/o/o/poorvididi') in /var/wkscript/functions.php on line 250. Please, tell me what to do.