Email problems - newly transfered from other host


DNS has propagated.

However, I cannot access either POP3 email or webmail. I can access the webmail site OK, but get a “Connection dropped by imap-server” error. Pop3 connect attempts (using Mac Entourage) result in a “Connection to the server failed or was dropped” error. I also cannot send.

Both the user name m631xxxx and password are entered correctly. There is no MB usage showing on the mail server, although delivery to my previous host has ceased. I’ve filed a trouble ticket, but hoping someone has an answer before I have to wait many hours for resolution.


I seem to be having a similar problem.

I CAN RETRIEVE my messages using POP3 but I am UNABLE TO SEND mail. I have the user name and pw correct for the SMTP verification, but it claims I don’t have a valid user/pw. I am using “” as my incoming and outgoing mail server. I have tried it out with multiple email clients different OSes. I can retrieve, so I know I have the user/pw correct.

It did appear to be functioning on Friday.

I can retrieve and send with the webmail client.

  1. Is your ISP blocking port 25? If so, and you don’t want to use their server, user port 587 instead
  2. Make sure you enable SMTP authentication; this is not “secure authentication” this is just where the server asks you for your username and password when you go to send a message, in Mozilla Suite this is just “server requires username and password”
  3. See


Also, if you know how to use TELNET, you can debug SMTP problems relatively easily by trying to send messages by hand. (Also IIRC Lookout/Lookout Express has options to log sessions)
(WinXP: go to Start > Run, type in cmd, or Start > All Programs > Accessories > Command Prompt, what you type is in bold)

[code]Prompt>telnet 587
EHLO username
250-SIZE 40960000
250 Ok
250 Ok
354 End data with .
[b]Subject: This is a test

250 Ok: queued as E76F5238CB
221 Bye

Connection to host lost.[/code]
:cool: Perl / MySQL / HTML CSS


I think you solved it!

Thanx Atropos7!

I now have an understanding why they block port 25. What happens if they start to block 587 to accomplish the same thing? Or is port 587 only used by DH?

Woo…Thanks for the telnet tip too. I am pretty green with telnet, but I will definitely look at what you posted.


All seem to be working now; possibly, email servers took a little longer to propagate; I had no response to my TT, so I’m assuming it was delayed propagation (48 hours).

For the other user encountering send problems, I have my outgoing set to, “sending SMTP server requires authentication” - “same as outgoing” in advanced account options. There was no need to use port 587 here; 25 worked just fine.


If you are familiar with US postal service, perhaps this analogy helps

  1. You give message to mailman
  2. mailman drives it to local postal center
  3. postal center transports it to remote postal center
  4. mailman picks up message from remote postal center
  5. mailman delivers it to recipient

So we have two types of connections here: public to postal service (#1, #5) and then
postal service to postal service (all others).

What happened with Internet mail though is that anybody could have sent messages claiming to be from one postal center to another, there was no checks to make sure a message actually originated at a customer > mailman connection, etc. Port 25 is postal service connections, Port 587 is designated for customer > postal service connections, so to speak. Analogy is not perfect, step #5 is done with POP3/IMAP and might not be a #4, not sure as I don’t run mail servers myself.

:cool: Perl / MySQL / HTML+CSS


Port 25 is the standard port used for all email transmissions. Due to the proliferation of email viruses and spam, many ISPs have started blocking port 25 to prevent their users’ machines from being hijacked in that way. Port 587 is also a standard for client->server email transmissions, but it is not very widely used. We have opted to support it to get around the blockings of port 25. It is possible and maybe even likely that port 587 will be blocked by ISPs at some point in the future, in which case we’d have to start supporting some other port as well.

  • Dallas
  • DreamHost Honcho


Port 587 blocking is a lot less likely, though. The reason providers block port 25 outbound is because spammers can send mail direct to MX; when submission is implemented properly (it’s not currently in our case, but could be if spammers started hitting us that way), only authenticated users can send via the message submission port (587) - no inbound mail destined for local users / domains would be accepted.

So the problem that blocking port 25 outbound “fixes” isn’t really a problem with port 587.