On webmail every user gets error "ERROR: Message not sent. Server replied: 354" while sending mails.
But mails are sent properly and reaches properly.
Can you tell me where is problem, and why it is occurred?
UPDATE: I found in some resources that this is not an error but standard information message. On the other side, it's annoying. Can you tell me if it is a true, and if it is how can I avoid it?
Your webmail program is badly written and thinks that the response code 354 is an error, even though it isn't.
This is what the SMTP conversation looks like (S = server, C = client)
S: 220 foo.com Simple Mail Transfer Service Ready
C: EHLO bar.com
S: 250-foo.com greets bar.com
S: 250-8BITMIME
S: 250-SIZE
S: 250-DSN
S: 250 HELP
C: MAIL FROM:<Smith@bar.com>
S: 250 OK
C: RCPT TO:<Jones@foo.com>
S: 250 OK
C: DATA
S: 354 Start mail input; end with <CRLF>.<CRLF>
C: Blah blah blah...
C: ...etc. etc. etc.
C: .
S: 250 OK
C: QUIT
S: 221 foo.com Service closing transmission channel
As you see, the code 354 means "OK, we're done with the information about sender and recipient, now give me the actual mail". However, your webmail system has been coded to think that only response codes starting with a 2 means "succeeded", so it takes any other code to mean that there's a problem. Whoever wrote the webmail program needs to go back and read RFC 5321 again and then fix the bug.
