Troubleshooting SMTP problems
This article covers several common SMTP (outgoing email) errors and possible solutions. Feel free to skip to the section that seems most relevant to the error you are experiencing.
Reproduce the problem
5.7.1 Relaying denied
- Make sure your email software is set to use password authentication for your outgoing (SMTP) server. This is not something that is enabled in Apple mail products by default! You should have your full email address entered for the username, and your email password for the password. Please check the following article for instructions for several common email programs:
- If you recently migrated this domain to (mt) Media Temple, please allow 24-48 hours for DNS propagation. In the meantime, you can use your mail access domain for your outgoing server instead.
- If you recently migrated this domain to (mt) Media Temple, please allow 24-48 hours for DNS propagation. In the meantime, you can use your IP address for your outgoing server instead, although I recommend switching back to your domain name as soon as DNS is resolving properly.
- This is essentially a "relaying denied" error from a (dv) Dedicated-Virtual Server running qmail. See the previous section for instructions regarding email client settings and DNS propagation.
- Your mail service for the sending domain in Plesk may not be enabled.
- Log into Plesk as the root or admin user.
- Click on Domains on the left.
- Click on the domain in question.
- Click on Mail.
- Make sure the mail service is enabled. You should see the option to Switch Off (meaning that it is currently on). If instead it says Switch On, click Switch On to enable the mail service.
- Next, we're going to make sure the mail service is enabled for the entire server. Follow Steps 1, 2, and 5 from the Plesk 8.6 documentation:
- Plesk documentation
- Do NOT select closed, and DO select authorization is required and SMTP authorization.
- You can also check your mail logs to see if mail is enabled for your domain.
- Run the following SSH command to see a live log of outgoing messages on your server:
tail -f /usr/local/psa/var/log/maillog
- Now, try sending your email again. If you see output similar to the following:
- First, close the log with CTRL-C.
- Then, run this command to check your allowed recipients:
- If the sending domain name is not listed, you will need to enable mail for the domain in Plesk, as described above.
Incorrect username or password
You may get a popup saying "Enter network password" if you use Outlook.
- Use your full email address for your username - it should look like firstname.lastname@example.org.
- Test your username and password in webmail at http://example.com/webmail. Replace example.com with your own domain.
- Test your username and password in webmail at http://webmail.example.com. Replace example.com with your own domain.
- Reset your email password. See (gs):Reset email password for assistance.
- Reset your email password. See (dv):Reset email password for assistance.
- In Apple Mail especially, try re-typing your username and password, even if they are correct. Sometimes the stored password keychain gets corrupted. See the troubleshooting section of our Apple Mail setup article for a more in-depth discussion of this problem.
Server not found
- Make sure you are online. If you're reading this article right now, you are most likely online. You can also try visiting your favorite web page.
- If the email address is at a new domain or one that you've recently pointed to (mt) Media Temple, your DNS change may not have propagated yet. DNS typically takes 24-48 hours to propagate. You can use your mail access domain at any time.
- If the email address is at a new domain or one that you've recently pointed to (mt) Media Temple, your DNS change may not have propagated yet. DNS typically takes 24-48 hours to propagate. You can use your IP address in the meantime, although I recommend switching back to your domain once the DNS change has propagated.
- Use password authentication, not any other kind. Please check the following article for instructions for several common email programs:
- The standard outgoing port (25) may be blocked by your Internet Service Provider. See Checking your outgoing mail server (Is Port 25 blocked?) for testing. If Port 25 is blocked, you can use Port 587 for outgoing email instead. You can switch your local email client to use Port 587 by following the appropriate guide here:
- The standard outgoing port (25) may be blocked by your Internet Service Provider. See Checking your outgoing mail server (Is Port 25 blocked?) for testing. If Port 25 is blocked, you can use Port 587 for outgoing email instead. First, you should enable Port 587 on your server:
- (dv) Add an Alternate SMTP Mail Port
- Then, switch your local email client to use Port 587 by following the appropriate guide here:
- Set up third-party email applications - Tip: scroll to the bottom of the article for a quick guide on changing your outgoing port.
Mailbox full / Quota Exceeded / Could not create output file
- Typically, this error indicates that the recipient's mailbox is full. You should receive the same error if you try to send to that particular recipient from a different email address. Please let them know about this problem.
- It's also possible to receive a disk space error if you store a copy of sent messages on the server for that mailbox, and the mailbox is nearing its capacity.
- See the Plesk 8.6 documentation for instructions on where to configure a quota for a mailbox. You can raise this quota if desired.
Rejected: User does not exist / No such address
- This error indicates that the recipient address may be misspelled, or may recently have been deleted as a mailbox on the recipient side. If your recipient has recently changed their DNS or their mail provider, you may need to wait 24-48 hours for their address to be switched to their new server.
Incorrect SMTP Configuration Files
Make sure your SMTP configuration files are present and configured correctly.
You can also rebuild your mail configuration files with the following command:
- Run the following command in SSH:
ls -l /etc/xinetd.d/smtp*
- You should see the following results:
-rw-r--r-- 1 root root 416 Sep 2 15:20 /etc/xinetd.d/smtp_psa -rw-r--r-- 1 root root 417 Sep 2 15:20 /etc/xinetd.d/smtps_psa
The names should have underscores, and the permissions and ownership should match those shown above.
- If underscores are missing, you can restart the mail service with the following command:
/usr/local/psa/admin/bin/mailmng -o ; /usr/local/psa/admin/bin/mailmng -p ; /etc/init.d/xinetd restart ; /etc/init.d/qmail restart
For more information, please read this article: Troubleshooting email.
Email taking too long to send
You should check your mail queue to see if you have more than a few messages waiting to go out. Anything over 100 messages in the queue at once is not desirable.
If you or one of your clients are sending a mass email, you should look into reducing the number of emails sent at one time. If instead you suspect that your server may be sending spam, see (mt) Security Resources.
If your specific error isn't shown here, or none of the solutions here are working for you, you should at least be able to narrow down whether your problem is being caused by a server issue, a network issue, or an email client issue. Please see our practical guide to troubleshooting walkthrough to perform some additional basic tests.