536, 550, 551, 552, 553 FTP Response Codes
Syntax error, command unrecognized, and the requested action did not take place. This may include errors such as command line too long.
536 FTP Response code
A 536 response code may be sent in response to a PROT command when the requested protection level is unsupported by the current security mechanism. It is a permanent negative response, which means the client is discouraged from sending the command again since the server will respond with the same response code. Negotiating a different security mechanism using the AUTH command can result in a different response code.
Example response
536 Requested PROT level not supported by mechanism.
Possible command:
550 FTP Response code
A 550 response code may be sent in response to any command requiring the server to access a local file. It is a permanent negative response, which means the client is discouraged from sending the command again since the server will respond with the same response code. It is usually due to a command requiring access to a file that does not exist or that the user does not have access rights to.
Example response
550 Requested action not taken; file unavailable…
Possible commands:
551 FTP Response code
A 551 response code may be sent in response to any command requiring the server to store information locally. 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 response code. It is only applicable when the page file structure is being used (through a STRU P command).
Example response
551 Requested action aborted: page type unknown.
Possible commands:
552 FTP Response code
A 552 response code may be sent in response to any command requiring the server to store received information locally. It is a permanent negative response, which means the client is discouraged from sending the command again since the server will respond with the same reply code. It usually indicates that the logged in user has exceeded the storage space allocated to their user account by the administrator.
Example response
552 Requested file action aborted; Exceeded storage allocation.
Possible commands:
553 FTP Response code
A 553 response 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.
Example response
553 Requested action not taken; File name not allowed.
Possible commands:
See also
- 110, 120, 125, 150 FTP response codes
- 202, 211, 212, 213 FTP response codes
- 214, 215, 220, 221 FTP response codes
- 225, 226, 227, 230 FTP response codes
- 232, 234, 250, 253, 257 FTP response codes
- 331, 332, 334, 336, 350 FTP response codes
- 401, 421, 425, 426 FTP response codes
- 431, 450, 451, 452 FTP response codes
- 500, 501, 502, 503, 504 FTP response codes
- 530, 532, 533, 534, 535 FTP response codes
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