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Microsoft Outlook

Autodiscover Notice

The Autodiscover feature only works with Outlook versions up to and including 2019. Newer versions (2021, Microsoft (Office) 365, and the new Outlook) no longer support Autodiscover for mailcow and require manual configuration.

This is not a mailcow bug, but a result of changes introduced by Microsoft.

This only applies if your server administrator has not disabled EAS for Outlook. If it is disabled, please follow the instructions for Outlook 2007 instead.

Warning

mailcow's ActiveSync support does not work reliably with Outlook on Windows. We strongly discourage using this setup.

Starting with Outlook 2019 (including Microsoft (Office) 365 and the new Outlook), ActiveSync is no longer functional with mailcow. Microsoft has disabled basic authentication for ActiveSync in these versions and now requires OAuth2 – a method that is incompatible with mailcow.

To manually set up EAS, launch the legacy setup assistant located at C:\Program Files (x86)\Microsoft Office\root\Office16\OLCFG.EXE. If the application opens, continue with step 4 from the Outlook 2013 instructions. If it fails to launch, disable the simplified account creation assistant and follow the Outlook 2013 setup guide.

  1. Start Outlook.
  2. If this is the first launch, the account setup wizard will appear. In this case, proceed to step 4.
  3. Open the File menu and click Add Account.
  4. Enter your name, email address, and password. Click Next.
  5. If prompted, re-enter your password, enable Remember my credentials, and click OK.
  6. Click Allow.
  7. Click Finish.

Autodiscover Notice

The Autodiscover feature only works with Outlook versions up to and including 2019. Newer versions (2019, 2021, Office 365, and the new Outlook) do not support mailcow Autodiscover and require manual setup.

This is not a mailcow issue, but the result of Microsoft’s changes.

To use EAS, start the legacy configuration assistant at C:\Program Files (x86)\Microsoft Office\root\Office16\OLCFG.EXE. If the application launches, proceed with step 4 from the Outlook 2013 instructions.

If it doesn’t open, you can disable the simplified account assistant and follow the instructions for Outlook 2013.

The new Outlook (pre-installed on Windows)

Caution regarding the new Outlook

Login credentials entered in the new Outlook are transmitted to Microsoft and processed in their data centers. For more information, see: https://www.heise.de/news/Microsoft-krallt-sich-Zugangsdaten-Achtung-vorm-neuen-Outlook-9357691.html

We strongly advise against using the new Outlook due to security concerns.

Warning

The new Outlook does not support CalDAV or CardDAV calendars – neither natively nor via Outlook CalDav Synchronizer.

If you still want to use the new Outlook, follow these steps:

  1. Launch the new Outlook.
  2. If no account has been added yet, the setup wizard will open automatically. In that case, skip to step 5.
  3. Click the gear icon in the top-right corner to open the settings.
  4. Navigate to Accounts > Your Accounts, then click Add Account on the left.
  5. Enter your email address and click Next.
  6. Choose IMAP from the list of providers.
  7. Enter the password for your email account in the Password field.
  8. For the IMAP Incoming Server, enter the FQDN of your mailcow server (e.g. mail.example.com).
  9. Use port 993 (IMAPS) in most cases.
  10. The Secure connection type should be SSL/TLS (for IMAPS) or STARTTLS (for plain IMAP), depending on the port.
  11. Re-enter your email address as the SMTP Username (if not prefilled).
  12. Enter your email password again as the SMTP Password.
  13. The SMTP Outgoing Server should again be your mailcow server's FQDN (e.g. mail.example.com).
  14. Use port 587 for SMTP submission.
  15. The Secure connection type should be SSL/TLS (for SMTPS/submission) or STARTTLS (for SMTP).
  16. Click Next to complete the setup.

Note

During the setup process, Microsoft may ask about privacy preferences. Decide for yourself whether and what to share.

Outlook 2007 or newer on Windows (Calendar/Contacts via CalDav Synchronizer)

Warning

This guide is not compatible with the new Outlook.

  1. Download and install Outlook CalDav Synchronizer.
  2. Start Outlook.
  3. If this is the first time launching Outlook, the account setup wizard will appear. In this case, proceed to step 5.
  4. Go to the File menu and click Add Account.
  5. Enter your name, email address, and password. Click Next.
  6. Click Finish.
  7. Go to the CalDav Synchronizer tab and click Synchronization Profiles.
  8. Click the second button at the top (Add multiple profiles), select SOGo, and click OK.
  9. Click Fetch settings from IMAP/POP3 account.
  10. Click Discover resources and map to Outlook folders.
  11. In the Select Resource window, choose your main calendar (usually Personal Calendar), click ..., assign it to the Calendar folder, and click OK. Repeat the process for Address Books and Tasks, assigning only one resource per folder type.
  12. Close all windows by clicking OK.

Outlook 2011 or newer on macOS

The macOS version of Outlook does not support synchronization of calendars or contacts with mailcow and is therefore not recommended.