outlook email will not set up in outlook 2016 desktop

Dear Dave, 

Thank you for posting to the Microsoft Q&A forum. 

I understand that you are facing issues adding your Outlook email address to the Outlook 2016 Desktop version. Dealing with setup errors is certainly frustrating, and we appreciate you trying both the automatic and manual methods already. 

We will focus on the most effective steps to get past the authentication barrier. 

1. Clear Credentials and Use an App Password 

These addresses stored password conflicts and 2FA requirements, which are the most common causes of authentication errors. 

Disclaimer: You will only remove entries related to Office or Outlook in the Credential Manager. This does not affect your main Windows sign-in password. 

1. Clear Stored Credentials: Close Outlook 2016 completely > open Credential Manager in Windows Search, and under Windows Credentials, Remove any entries referencing Outlook or MicrosoftOffice. 
2. Generate an App Password: If you have Two-Factor Authentication (2FA) enabled on your Microsoft account, Outlook 2016 will require a special App Password. Go to your Microsoft Account Security Basics page, find the App passwords section, and Create a new app password. Use this generated password instead of your main password when attempting to set up the account. 

2. Update Outlook 2016 for Modern Authentication 

Ensure your version of Outlook 2016 has the latest fixes for Modern Authentication. 

1. Go to File > Office Account. 
2. Under Product Information, click Update Options > Update Now. 
3. Once updated, try forcing the modern authentication flow: Close Outlook, go to Windows Control Panel > Mail (32-bit) > Show Profiles > Properties > Email Accounts, select your Outlook account (if listed), and choose Repair. 

Note: The Repair process will attempt to reset your account's connection method. It may ask you to re-enter your password (use the App Password here if applicable) and should ideally trigger the modern authentication pop-up. 

3. Advanced Step: Force Modern Authentication via Registry Edit 

If the steps above fail to resolve the blank screen or password loop, we can apply a Registry edit to force Outlook 2016 to use the required modern authentication protocols. 

Disclaimer: Registry edits involve making changes to a core part of the operating system. Please follow the instructions exactly. We recommend backing up your registry before proceeding. 

1. Exit Outlook 2016. 
2. Press Windows Key + R, type regedit, and press Enter to open the Registry Editor. 
3. Navigate to the following key: HKEY_CURRENT_USER\Software\Microsoft\Exchange 
4. Right-click in the right pane, select New > DWORD (32-bit) Value. 
5. Name the new value: AlwaysUseMSOAuthForAutoDiscover 
6. Double-click the new value and set the Value data to 1. 
7. Exit the Registry Editor and restart your computer. 

After performing the registry edit, try the automatic account setup in Outlook 2016 again. 

Please try these steps and let me know the result, especially if you receive a new or different error message. We look forward to your response. 

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