SMTP Error Codes – How annoying can it be when your email program gives you a could not send message followed by a non descript error message.
All SMTP errors follow a certain structure which can make understanding error codes much easier once understood.
The structure of error codes consists of three numbers.
Our first number tells us if the server accepted our request.
And there are 5 possible notifications..
- a) Message has successfully completed task without errors.
- b) Mail server has accepted task but has taken no action.
- c) A confirmation message is required.
- d) Mail server has understood request but requires more information to complete it.
- e) Mail server has encountered temporary failure. If command is repeated without
- f) change it. might be completed, try again.
- g) Mail server has encountered fatal error, your request cannot be processed.
The second number gives us 4 possible usable notifications..
Syntax error Information, the status of the connection, the status of the mail server
- 211 system status code
- 214 help message
- 220 service ready
- 221 service closing transmission channel
- 250 requested mail action okay, completed
- 251 user not local, but will forward to
- 354 start mail input, end with
- 421 service not available, closing transmission channel
- 450 requested mail action not taken: mailbox unavailable
- 451 requested action aborted, local error in processing
- 452 requested action not taken, low system disk storage
- 500 syntax error or unrecognized command
- 501 syntax error in command line
- 502 command not implemented, due to above
- 503 bad sequence of commands
- 504 command parameter not implemented
- 550 requested action not taken: mailbox unavailable
- 551 user not local, try again
- 552 requested mail action aborted, exceeded mailbox storage allowance
- 553 requested action not taken, invalid mailbox name
- 554 Transaction failed
Many SMTP error codes are usually very simple fixes, so before you begin to look into why your getting a particular error make sure you have checked the basics it can save a lot of time.
Do you have a Working Internet Connection, Double check Login credentials, Correct Server configuration, Does your ISP have mail server problems, Are you downloading a very big email using a slow connection, be prepared to wait, Is your Winsock File Corrupt
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