Plesk 8.1 FTP Backup Manager cannot access folder on remote back up server

[Lance Cooke]

Hello,

I continue to get the following response from our FTP server (FileZilla server residing on XP) while trying to set up FTP Account Settings in Plesk's Backup Manager (residing on a remote Linux box)- I have double-checked the permissions on the back up folder (called PleskBak) many times.

(000110) 9/9/2009 14:00:07 PM - (not logged in) (*.*.*.*)> Connected, sending welcome message...
(000110) 9/9/2009 14:00:07 PM - (not logged in) (*.*.*.*)> 220-FileZilla Server version 0.9.24 beta
(000110) 9/9/2009 14:00:07 PM - (not logged in) (*.*.*.*)> 220-written by Tim Kosse (Tim.Kosse@gmx.de)
(000110) 9/9/2009 14:00:07 PM - (not logged in) (*.*.*.*)> 220 Please visit http://sourceforge.net/projects/filezilla/
(000110) 9/9/2009 14:00:07 PM - (not logged in) (*.*.*.*)> USER ftpUSER
(000110) 9/9/2009 14:00:07 PM - (not logged in) (*.*.*.*)> 331 Password required for ftpUSER
(000110) 9/9/2009 14:00:07 PM - (not logged in) (*.*.*.*)> PASS ****
(000110) 9/9/2009 14:00:07 PM - ftpUSER (*.*.*.*)> 230 Logged on
(000110) 9/9/2009 14:00:07 PM - ftpUSER (*.*.*.*)> PWD
(000110) 9/9/2009 14:00:07 PM - ftpUSER (*.*.*.*)> 257 "/" is current directory.
(000110) 9/9/2009 14:00:07 PM - ftpUSER (*.*.*.*)> DELE pleskBak/_0bb19d1501e8ec0129e342b86764a43f
(000110) 9/9/2009 14:00:07 PM - ftpUSER (*.*.*.*)> 550 File not found
(000110) 9/9/2009 14:00:07 PM - ftpUSER (*.*.*.*)> disconnected.

my emphasis is on these lines:

(000110) 9/9/2009 14:00:07 PM - ftpUSER (*.*.*.*)> DELE pleskBak/_0bb19d1501e8ec0129e342b86764a43f
(000110) 9/9/2009 14:00:07 PM - ftpUSER (*.*.*.*)> 550 File not found

Why is Plesk's FTP Account Settings issuing a DELE command when trying to write test data to the server? and what on earth does "_0bb19d1501e8ec0129e342b86764a43f" represent?? is the backup utility possibly broken and I am barking up the wrong tree?
Any guidance is appreciated.

Lance