KB / Email / POP3/IMAP/SMTP Servers
From DreamHost
Basic information about incoming/outgoing servers for your email configuration pleasure.
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IMAP-IDLE command is supported
The IMAP-IDLE command is now installed and available on all plans. This feature is popular for those to wish to "push" email to their PDA/Phones. There are no additional settings to configure in the control panel or in webmail...if you have the PDA/Phone set up correctly, the email will be pushed to you.
--- Update: IMAP-IDLE is NOT working correctly on Dreamhost mail servers. No ETA on a fix at the moment. ---
Is there a size or attachement size limit for email?
Yes. Our mail servers will reject messages greater than 40 Mb for either incoming or outgoing mail. This limit applies to the entire message size, regardless of content. This means, you can send or receive a message with or without attachment, but the total size cannot exceed 40 Mb per message.
For files larger than this, you should upload the file to an anonymous FTP server or to your website and send the recipient a link to the file.
What is an SMTP server?
It is an Internet email server that knows how to send your email on its way to its proper destination.
In order for your email program on your local computer to successfully send email, it must have an Internet connection plus an "SMTP" server address that it is allowed to send mail through.
When you host with us, mail.yourdomain.com is the address of the SMTP server you use!
What is the name of my outgoing mail (SMTP) server?
Both your incoming and outgoing mail servers are just
mail.example.com
Where example.com is replaced by your domain you host with us.
Also, some ISPs block port 25! You may have to use your ISPs SMTP server instead of ours 'or use the alternate port 587 if this is the case. Your ISPs internal SMTP server’s domain name address is most likely "mail.isp.com" or "smtp.isp.com". You can still have your from email address be @yourdomain.com even if you're using your isps SMTP server fortunately!
Since few ISPs block ports other than 25, use of the alternate port 587 might be better. Especially if you're using a laptop or other portable device that may be used on alternate internet connections, setting the port to 587, will relieve you of changing your settings for each new location.
An additional workaround is to use secure SMTP, if your mail client supports this. See Secure_E-mail for more information on secure SMTP.
NOTE.. you must set your username for the outgoing SMTP server (in Netscape for example under "Outgoing Mail Server User Name) to be the same as your incoming mail server username. It will then ask you for your password the first time you send mail. We use Authenticated SMTP.
NOTE FOR EUDORA USERS: As reported by a user ... "In Eudora each of the personalities needs to have a server specified in the incoming mail section. Even if it doesn't check the email on that account." If you are having trouble sending email from one of your domains, this may be the cause.
Does my ISP block port 25?
Some Internet providers have recently started blocking port 25 in an attempt to help prevent direct to MX spamming, and abuse of open proxies / relays from their dialup and broadband customers.
Some major ISPs that do this (and the address of their SMTP server) are:
| ISP | SMTP Server |
|---|---|
| People PC | mail.peoplepc.com |
| Optimum Online | mail.optonline.net |
| MSN | smtp.email.msn.com |
| EarthLink | smtpauth.earthlink.net |
| Verio | mail.verio.net |
| Comcast / ATTBI | smtp.comcast.net |
| Cox | smtp.west.cox.net/smtp.east.cox.net |
| Telus | smtp.telus.net (No auth. required) |
| Charter | stmp.charter.net |
| Grande Communications(Tech Support says that it is available for unblocking upon request) | mail.grandecom.net |
| Mediacom | mail.mchsi.com |
| Telenet | uit.telenet.be |
| Shaw | shawmail ("shawmail" is an alias that then points you to your city-specific mail server) |
| CableOne | mail.cableone.net |
| Many others | [smtp/mail].example.com |
Fortunately it seems that AOL does NOT do this (as of Feb 2002)!
Unfortunately a side-effect of this practice is that it prevents users from accessing our SMTP servers. If you are getting error messages when you try sending mail which state that smtp.domain.com is not responding or not found, contact your ISP, and find out if they're blocking port 25. If they are, you can probably send outgoing mail through their outgoing mail servers, or you can try using port number 587 instead.
Sometimes, however, an ISP will not allow email to be sent through their SMTP server with a different domain. In other words, you may only be able to use their SMTP server if you have your reply address set to your ISP-based email address, not your custom domain name address that you have at DreamHost.
DreamHost does support message submission protocol, as per RFC 2476. This means that you can use port 587 for outgoing mail. If your mailer supports it, you can simply set it to send outgoing mail on this port instead of port 25.
What is the name of my incoming mail (POP/IMAP) server?
Both your incoming and outgoing mail servers are just
mail.domain.com
Where domain.com is replaced by your domain you host with us.
IMAP/SSL Domain Mismatch Errors
If you try to use IMAP/SSL to access mail at "mail.yourdomain.com", you will be presented with a "domain mismatch" warning. This is because DreamHost's IMAP SSL Certificate is for mail.dreamhost.com. For some users, setting your IMAP server to mail.dreamhost.com may work to avoid this error. However, not all users can log into the mail.dreamhost.com mailserver. If you cannot log into mail.dreamhost.com, reset your IMAP server to mail.yourdomain.com and look for a way to turn off the error. You should only turn off this error if you trust that the server your are connecting to is the correct server. If you blindly trust unmatching SSL certificates, you can easily be tricked by a malicious certificate.
If you know what a "hosts" file is and have access to edit the one on your computer, you can add the IP of mail.yourdomain.com to your hosts file and point mail.dreamhost.com at it. YMMV if you ever need to access anything that's actually located on mail.dreamhost.com, but I haven't run across anything yet, personally.
In some mail clients, you can turn off the warning about a domain mismatch. For Mozilla Thunderbird, check out this extension which adds a box to the warning dialog box to ignore that warning only. There are solutions to other clients as well. If you have one, please list it here.
The Evolution e-mail client will not even attempt to communicate with mail.dreamhost.com over IMAP/TLS unless you create aforementioned entry in the /etc/hosts file so that mail.dreamhost.com points to the IP address of mail.YOURDOMAIN.com. Evolution will simply fail to negotiate a SSL connection.
