Disabling of Plaintext Authentication for E-mail

Published on: March 2, 2016

Currently, our Business and Reseller servers allow plaintext authentication for sending and receiving mail. We will be updating the configuration where this is concerned to make e-mail more secure on the server. We will be making the following changes:

  • Receiving e-mail
    • The allowing of plaintext authentication for POP3 and IMAP will be disabled.
    • Connections to the server on ports 110 and 143 will not be allowed.
  • Sending e-mail
    • E-mail clients will be required to connect with SSL or issue the STARTTLS command before being allowed to authenticate.

With that said, we recommend the following settings for your e-mail clients (Outlook, Thunderbird, etc.)

Secure SSL/TLS Settings (Recommended)
Username: Your full email address.
Password: Use the email account’s password.
Incoming Server: YOUR SERVER HOSTNAME
IMAP Port: 993
POP3 Port: 995
Outgoing Server: YOUR SERVER HOSTNAME
SMTP Port: 465
Authentication is required for IMAP, POP3, and SMTP.

For your convenience, we explain below how to set up a new account with the correct settings and modify an existing account for both Thunderbird and Outlook.


New account setup in Thunderbird
1. Open up Thunderbird.
2. In the left sidebar click Local Folders.
3. When the right panel loads, under Create A New Account click Email. This will bring up the Mail Account Setup screen.
4. Enter your name, Email address, and Password in the appropriate fields and click Continue.
5. Thunderbird will automatically detect the following recommended settings.
  • Incoming: IMAP, server hostname*, STARTTLS
  • Outgoing: SMTP, server hostname*, STARTTLS
  • Username: Your full e-mail address.
  • * “Server hostname” would be something like “dime192.dizinc.com”.

6. Click Done.
7. If you get the Add Security Exception prompt, click Confirm Security Exception.


Modify an existing account in Thunderbird.
1. Open Thunderbird.
2. In the left sidebar, click the top level folder for the account you want to modify.
3. In the right panel, click View settings for this account.
4. When the Account Settings window opens, in the left pane click Server Settings under the account you are modifying.
5. If your Server Type is IMAP, make sure the port is 993. If your Server Type is POP3, make sure the port is 995.
6. Change Connection Security to SSL/TLS, if it is not that already.
7. To update the Outgoing Mail Server, click Outgoing Server (SMTP) in the left pane.
8. On the list of SMTP servers, select the server in question and click Edit.
9. Make sure the port is 465.
10. Make sure the Connection security is SSL/TLS.
11. Click OK to close the SMTP Server window.
12. Click OK to close the Account Settings window.


Add new e-mail account in Outlook.
1. Open Outlook.
2. Click the File tab at the top.
3. Click Account Settings.
4. On the Account Settings screen, click New.
5. Enter your name, E-mail Address, and Password in the appropriate fields and click Next.
6. Outlook will auto discover the settings. If you are prompted with a security alert, click Yes to proceed.
7. Once the account is successfully added, click Finish.


Change existing account in Outlook.
1. Open Outlook.
2. Click the File tab at the top.
3. Click Account Settings.
4. On the Account Settings screen, click Change.
5. On the Change Account screen, click More Setings…
6. On the Internet E-mail Settings screen, click the Advanced tab.
7. If your incoming server is IMAP, make sure the port is 993. If your incoming server is POP3, make sure the port is 995.
8. For Incoming and Outgoing, set the type of encrypted connection to TLS by selecting that option in the drop down menu.
8a. Certain versions of Outlook are not compatible with the TLS encryption protocol, using SSL in this case is an acceptable alternative.



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