550 Permission denied FTP

[munge83]

I am experiencing an strange error on Filezilla, I can't edit/remove any files.

By ssh I can remove/move/edit any files without restriction

Whats going on? How to solve?
Thanks

I had the same problem.
I was not able to change permissions or rename the files via FTP , so I checked the ownership of the files with ssh
# ls -l filename
result: -rw-r--r-- 1 root root 53 Apr 7 2011 filename

so the owner of all unziped files was root ,

I allsow checked the ownership of the folder public_html that server created and it was something like this
drwxrwxrwx 3 www-data www-data 4096 Nov 26 12:13 public_html

so I went out side the folder and all the files I neded to chang the ownership , the unziped files and applyed this to folder
chown -R www-data folder

after that I was able to change file permissions and rename files via FTP

Can someone confirm that is security safe method ?