Outlook AutoConfiguration Test Failed: How to Run and Interpret the Results

You may see an Outlook AutoConfiguration test failed error when your email account has connection problems. This diagnostic tool checks the settings Outlook uses to connect to your mail server. This article explains how to run the test and understand the detailed results it provides. You will learn to identify the root cause of common email setup failures.

What the Outlook AutoConfiguration Test Does

The AutoConfiguration test is a built-in diagnostic tool in Outlook for Microsoft 365 and other modern versions. Its primary job is to discover the correct server settings needed to connect your email account. When you add an account, Outlook automatically tries to find these settings. If this automatic setup fails, you get an error and must run the test manually.

The test works by querying your email provider’s domain using standard protocols like Autodiscover. It attempts multiple connection methods to locate the correct mail server addresses for IMAP, POP3, or Exchange, along with the right security and port settings. The test generates a log showing each attempt, making it clear which steps succeeded and which failed. This log is the key to fixing configuration problems.

When You Need to Run This Test

Run the AutoConfiguration test if you cannot send or receive email, or if Outlook repeatedly asks for your password. It is also useful after changing your email password on the server side, or if you have moved to a new computer. The test helps when automatic account setup fails completely, leaving you with a generic error message that offers no details.

Steps to Run the Outlook AutoConfiguration Test

Follow these steps to start the test and examine its output. You do not need to have the main Outlook window open.

1. Access the hidden test menu
   Close the main Outlook window if it is open. Find the Outlook icon in your Windows system tray, near the clock. Hold down the Ctrl key on your keyboard, then right-click the Outlook icon. A special context menu will appear.
2. Start the test client
   From the menu that appears, select Test E-mail AutoConfiguration. A new dialog window will open. Ensure the email address you want to test is shown in the E-mail Address field.
3. Configure test options
   Uncheck the box for Use Guessmart. Check the boxes for Use AutoDiscover and Secure Guessmart Authentication. Leave the password fields blank unless you are testing authentication specifically.
4. Run the test
   Click the Test button. Outlook will begin its diagnostic routine, attempting various connection paths to your email server. This may take a moment.
5. Review the log output
   Once complete, click the Log tab. This shows a line-by-line record of every connection attempt. Look for lines containing the word FAILED or error codes, as these indicate where the process broke down.
6. Check the final results
   Click the Results tab. This shows the server settings Outlook successfully discovered, such as the Server, Login, and Protocol for both incoming and outgoing mail. Verify these match your email provider’s recommended settings.

How to Interpret Common Test Results and Errors

Autodiscover Step Fails with a 0x800C8203 Error

This common error means Outlook could not contact the Autodiscover service for your domain. The cause is often a network or DNS issue. First, check your internet connection. If other websites load, the problem may be with your DNS settings. Try switching to a public DNS like Google’s (8.8.8.8) in your Windows network adapter settings. For corporate accounts, your IT department may need to verify the Autodiscover DNS record is correctly published.

Test Log Shows Authentication Failed

If the log shows an authentication failure, your username or password is incorrect, or the server rejects the login method. Confirm your password is correct on your email provider’s webmail page. In the test dialog, try entering your password before running the test. Check the Results tab to see which authentication method was discovered, such as NTLM or Basic Auth, and ensure it is supported by your provider.

Test Succeeds But Outlook Still Cannot Connect

Sometimes the test finds correct settings, but the main Outlook profile still fails. This usually means cached corrupted credentials or a profile issue. Go to Windows Control Panel, open Mail, and click Email Accounts. Select your account and click Repair. Alternatively, remove the account completely and re-add it, using the settings confirmed in the test’s Results tab for manual setup.

Outlook AutoConfiguration Test Modes Compared

Item	Autodiscover Mode	Guessmart Mode
Primary Method	Queries the official Autodiscover service via DNS or a known URL	Attempts to guess server names based on the email domain (e.g., mail.domain.com)
Accuracy	High, as it retrieves settings directly from the email provider	Low, relies on common naming conventions which may be wrong
Use Case	Standard for Microsoft 365, Exchange, and many modern hosted email services	Fallback method when Autodiscover is not configured; often used for older POP3/IMAP accounts
Security	Uses secure HTTPS connections by default	May attempt insecure connections unless Secure Guessmart is checked

After running the test, you can pinpoint exactly why your email account is not connecting. Use the information on the Log and Results tabs to correct server addresses or work with your IT support. For persistent issues, try creating a new Outlook profile via the Windows Mail control panel. An advanced tip is to use the Microsoft Support and Recovery Assistant tool, which can run deeper diagnostics and apply fixes automatically for many common Outlook problems.