backup problem

I got this error when backing up my virtualmin files:

Backing up AWstats configuration file ..
.. done

Creating final backup archive ..
.. archive failed!
/bin/sh: /root/backup/darkgroup.net.tar.gz: Not a directory

Backup failed! See the progress output above for the reason why.

I saw that there was already one who had this problem but seems never resolved...
I'm using the latest virtualmin version (3.12) on fedora core 5

Status: 
Closed (fixed)