Answer

100 Codes The requested action is being taken. Expect a reply before proceeding with a new command
110 Restart marker reply
120 Service ready in (n) minutes
125 Data connection already open, transfer starting
150 File status okay, about to open data connection

200 Codes The requested action has been successfully completed
200 Command okay
202 Command not implemented
211 System status, or system help reply
212 Directory status
213 File status
214 Help message
215 NAME system type (NAME is an official system name from the list in the Assigned Numbers document.)
220 Service ready for new user
221 Service closing control connection. (Logged out if appropriate.)
225 Data connection open, no transfer in progress
226 Closing data connection. Requested file action successful (file transfer, abort, etc.)
227 Entering Passive Mode
230 User logged in, proceed
250 Requested file action okay, completed
257 “PATHNAME” created

300 Codes The command has been accepted, but the requested action is being held pending receipt of further information
331 User name okay, need password
332 Need account for login
350 Requested file action pending further information

400 Codes The command was not accepted and the requested action did not take place
The error condition is temporary, however, and the action may be requested again
421 Service not available, closing control connection. (May be a reply to any command if the service knows it must shut down.)`
425 Can’t open data connection
426 Connection closed, transfer aborted
450 Requested file action not taken. File unavailable (e.g., file busy)
451 Requested action aborted, local error in processing
452 Requested action not taken. Insufficient storage space in system

500 Codes The command was not accepted and the requested action did not take place
500 Syntax error, command unrecognized. This may include errors such as command line too long
501 Syntax error in parameters or arguments
502 Command not implemented
503 Bad sequence of commands
504 Command not implemented for that parameter
530 User not logged in
532 Need account for storing files
550 Requested action not taken. File unavailable (e.g., file not found, no access)
552 Requested file action aborted, storage allocation exceeded
553 Requested action not taken. Illegal file name