http://www.howtoforge.com/forums/showpost.php?p=55492&postcount=25
I managed to stolve my similar problem by adding this directive to my proftpd.conf or proftpd_ispconfig.conf file (in the server section) Bind...
I had the same problem with my ISPconfig: could not update and temp dir wasnt present, used mkdir & chown to fix it. :)
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