Trouble connecting to openSSH SFTP server

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http://askubuntu.com – I've created an SFTP server using OpenSSH and configured a special user account with one folder access only using this how-to. When I run these commands I can connect to the server: sudo chown root:root /var/commons/ sudo chmod 755 /var/commons/ But when I try to modify files I get a permissions error which is solved by running this: sudo chown transferer:sftponly /var/commons/ sudo chmod 755 /var/commons/ Although I can modify files using the connected FileZilla, I cannot re-connect to the server again! What am I doing wrong and how do I correct this? My SFTP user account is transfer (HowTos)