Troubleshooting Tips for an Outlook TLS Error

Quick Tips

• TLS 1.2 and 1.3 are the current standard, so if you see any other you might have issues with your configuration.
• Try to exhaust common troubleshooting such as resetting your network connection, router, or PC.
• These settings are only available for a native Outlook account, not accounts that are imported into the Outlook app.

When trying to access your mail via Outlook, you may get an error message in the likes of “Your server does not support the connection encryption type you have specified. Try changing the encryption method.” But if you haven’t changed anything, you may need to perform some fixing. Here are the most common troubleshooting tips for an Outlook TLS error.

Fix 1: How to Fix Outlook TLS Error by Switching Between SSL and TLS

Sometimes the encryption type you’ve selected in Outlook doesn’t match what your mail server expects. If you have SSL selected but your server requires TLS (or vice versa), you’ll get an encryption error. Switching between the two can often work.

Step 1. Click on File in the top menu ribbon.

Step 2. Go to “Account Settings,” then select “Account Settings” again from the dropdown menu.

Step 3. Select your email account from the list and click “Change.”

Step 4. Go to the Advanced tab at the top of the settings window.

Step 5. Look for the section labeled “Use the following type of encrypted connection.” If it’s set to SSL, change it to TLS. If it’s set to TLS, try changing it to SSL.

Step 6. Click OK to save the changes, then close and restart Outlook.

Fix 2: Enable TLS 1.2 in Windows Internet Options

Even if Outlook is configured correctly, Windows might not have TLS 1.2 enabled. This is especially common on older computers which have upgraded from Windows 7.

Step 1. Hit “Win + R” to open the Run dialog.

Step 2. Type “inetcpl.cpl” and hit “Enter.” This opens “Internet Properties.”

Step 3. Click on the Advanced tab at the top of the window.

Step 4. Scroll down until you find the section with “Security” or “Use TLS.”

Step 5. Check the boxes next to “Use TLS 1.2” and “Use TLS 1.3.” Uncheck “Use SSL 3.0,” “Use TLS 1.0,” and “Use TLS 1.1” (if they are checked).

Step 7. Click “Apply” and then “OK” to save your changes.

Step 8. Restart your computer for the changes to take effect.

Fix 3: Update Outlook to the Latest Version

If you’re using an older version of Outlook, it might not support TLS 1.3 properly. Outlook versions from the 2010 era and earlier have limited TLS support.

Step 1. Open Outlook and click File from the menu.

Step 2. Look for an “Office Update” or “Check for Updates” option. Click on it if available.

Step 3. If updates are available, follow the prompts to download and install them. This might require a restart.

Step 4. Alternatively, if Outlook updates aren’t available, check for Windows updates.

Step 5. Click Check for updates and install any available updates.

Step 6. Restart your computer and try Outlook again.

If you have a really old version of Outlook that came with Microsoft Office, you might need to upgrade the entire suite.

Fix 5: Verify Correct Mail Server Settings

Sometimes the TLS error is caused by incorrect server settings. If your incoming or outgoing mail server address is wrong, or if you’re using the wrong port, you’ll get connection errors. Port 995 is typically used for POP3 with SSL, while port 587 is used for SMTP with TLS.

Step 1. Contact your email provider (Gmail, Outlook.com, your company, your hosting provider, etc.) and ask for the correct incoming and outgoing mail server settings.

Step 2. Open Outlook’s Account Settings (File > Account > Account).

Step 3. Select your email account and click “Manage.”

Step 4. Go to the Advanced tab and verify or change the values to the following:

• Incoming Mail Server (POP3 or IMAP) address
• Incoming server port (usually 995 for POP3 SSL, 993 for IMAP SSL)
• Outgoing Mail Server (SMTP) address
• Outgoing server port (usually 587 for SMTP with TLS).

Step 5. Restart Outlook and test your email connection.