Knowledgebase

While Linux does not have a single “default” email client, most popular distributions support applications like Thunderbird, Evolution, Geary, and KMail. This guide explains how to add your Office 365 email to these applications, as well as how to connect to Gmail from Linux.

1. Add Office 365 to Thunderbird (Most Popular Linux Mail App)

Thunderbird is available on nearly all Linux distributions and has full support for Office 365.

1. Open Thunderbird.

2. Go to Menu > New > Existing Mail Account.

3. Enter your Name, Office 365 email address, and password, then click Continue.

4. Thunderbird should automatically detect the correct Microsoft 365 settings:

   • Incoming (IMAP): outlook.office365.com — Port 993, SSL/TLS

   • Outgoing (SMTP): smtp.office365.com — Port 587, STARTTLS

5. Select IMAP (remote folders).

6. Click Done and complete any MFA/permissions if prompted.

✅ Your Office 365 mailbox will now sync with Thunderbird.

2. Add Office 365 to Evolution (GNOME Desktop)

Evolution integrates tightly with GNOME and supports Microsoft Exchange.

1. Open Evolution.

2. Go to Edit > Preferences > Mail Accounts > Add.

3. Select Exchange Web Services (EWS) as the account type.

4. Enter your Office 365 email address and password.

5. Evolution will auto-discover the server using Microsoft’s EWS.

6. Confirm and save the account.

✅ Your Office 365 mail, calendar, and contacts will now sync.

3. Add Office 365 to Geary (Lightweight Mail App)

Geary is lightweight and popular on Ubuntu-based distributions. It does not support Exchange natively, but you can use IMAP/SMTP.

1. Open Geary.

2. Go to Accounts > Add Account.

3. Select Other (IMAP/SMTP).

4. Enter the following details:

   Incoming (IMAP)

   • Server: outlook.office365.com

   • Port: 993

   • Encryption: SSL/TLS

   • Username: Full Office 365 email address

   • Password: Your email password

   Outgoing (SMTP)

   • Server: smtp.office365.com

   • Port: 587

   • Encryption: STARTTLS

   • Username: Full Office 365 email address

   • Password: Your email password

✅ Geary will now connect to your Office 365 account.

4. Add Office 365 to KMail (KDE Desktop)

KMail is the default KDE mail client, part of Kontact.

1. Open KMail.

2. Go to Settings > Accounts > Receiving > Add Account.

3. Choose IMAP.

4. Enter the IMAP details for Office 365:

   • Server: outlook.office365.com

   • Port: 993

   • Encryption: SSL/TLS

5. Go to Sending > Add Account and enter the SMTP details:

   • Server: smtp.office365.com

   • Port: 587

   • Encryption: STARTTLS

6. Save and test your connection.

✅ KMail will now sync with your Office 365 account.

5. Use Office 365 with Gmail on Linux (Web-Based)

If you prefer Gmail on Linux:

• You can add your Office 365 mailbox to Gmail via POP3 import or SMTP send-as in Gmail settings (see our Gmail setup guide for step-by-step instructions).

• Once added, Gmail can be accessed in any Linux browser or via web apps like GNOME Web/Epiphany or Chrome.

Troubleshooting Tips

• Authentication issues? If your organisation uses Multi-Factor Authentication (MFA), you may need to generate an App Password in Microsoft 365.

• Evolution issues? Make sure the evolution-ews package is installed (provides Exchange Web Services support).

• Thunderbird issues? Install the Owl for Exchange add-on if IMAP/SMTP doesn’t provide full functionality.

• Ensure your Linux system and email clients are updated to the latest version.

✅ You can now use your Office 365 email across Linux desktops with Thunderbird, Evolution, Geary, KMail, or Gmail in the browser.