553 FTP Reply Code - KB Article #1536Related Articles --
553 Requested action not taken; File name not allowed.
A 553 reply code may be given in response to any command requiring or supporting the use of a file name as a parameter. It is a permanent negative reply, which means the client is discouraged from sending the command again since the server will respond with the same reply code. It is usually due to the file name contained as a parameter violating the file naming policies existing on the server. Issuing the command again with a different file name may result in a different reply code.