Defaulting to non @outlook.* email address.

It seems that you're experiencing an issue where Outlook defaults to your @outlook address instead of your preferred custom email address on both mobile and PC applications. This can happen due to account settings or configurations within the Outlook application. Here are a few steps you can try to resolve this issue:

1. Check Account Settings in Outlook: Make sure that your preferred email address is set as the default in your Outlook account settings. You can do this by going to File > Account Settings > Account Settings and ensuring your preferred email is set as the default.
2. Remove and Re-add the Account: Sometimes, removing the account and re-adding it can help. Make sure to add your preferred email address during the setup process.
3. Update Outlook: Ensure that your Outlook application is up to date, as updates may include fixes for known issues.
4. Use the Correct Email Address: When setting up your account, ensure you are entering the exact preferred email address you want to use, as discrepancies can lead to defaults being set incorrectly.
5. Check for Multiple Accounts: If you have multiple accounts set up in Outlook, it may default to the first account listed. You may need to adjust the order or remove unnecessary accounts.

If these steps do not resolve the issue, consider checking the Microsoft support forums or contacting Microsoft support for further assistance.

References:

• Connection to Microsoft Exchange is unavailable error when a Microsoft 365 user tries to set up Outlook
• Outlook can't set up a new profile by using Exchange Autodiscover for an Exchange Online mailbox in Microsoft 365

Dear sharron,

Thank you for posting your question to the Microsoft Q&A forum. I understand how annoying it is when your Outlook apps persist in defaulting to your @outlook.com address, even though the Web version correctly uses your custom domain.

The reason this is happening is that Outlook apps handle "default" identities differently than the web version. The apps look strictly at the Primary Alias set on the backend of your Microsoft account. Because the @outlook.com address is likely still set as the Primary, the apps force that selection regardless of how you signed in.

To resolve this behavior, you need to change the setting at the account level. Please follow these steps:

Step 1: Change Your Primary Alias

1. Open a browser and navigate to account.microsoft.com/profile.
2. Click on "Edit account info" (usually on the right side).
3. You will see a list of all email aliases associated with your account. Find your custom email address in the list.
4. Click "Make primary" next to it.
   • Note: If your custom address is a third-party email (like Gmail or Yahoo) just linked to your Microsoft account, you may not be able to set it as a primary sending alias.

Important: This change can take 24 to 48 hours to fully update across all Microsoft servers. If you try to fix the app immediately, it might revert to the old setting.

Step 2: Remove and Re-add the Account

Once the 24 hours have passed, you need to force the app to recognize the new primary identity.

1. Open the Outlook app on your phone/computer.
2. Go to Settings > Accounts.
3. Select the account and tap Delete Account (or "Remove Account").
4. Restart your device (this clears the cached settings).
5. Open Outlook and add the account again, using your custom email address to sign in.

Please let me know if you run into any issues changing the alias setting!

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