How to fix error error-mutual-auth-failed in Windows 11

Solution Steps

1. 1 First, verify that the client and server are using the correct time. Press Windows key + I, go to 'Time & Language', and ensure 'Set time automatically' is on. Time skew can cause Kerberos authentication to fail.
2. 2 Check if the service principal name (SPN) is correctly registered. Open Command Prompt as administrator (right-click Start, select 'Terminal (Admin)'). Type 'setspn -L yourserviceaccount' and press Enter. This lists the SPNs associated with the service account.
3. 3 If the SPN is missing or duplicated, you need to fix it. To add an SPN, type 'setspn -A HTTP/myserver.domain.com yourserviceaccount' (replace with your actual service and account). To remove a duplicate, use 'setspn -D HTTP/myserver.domain.com yourserviceaccount'.
4. 4 If the service is running under a domain account, ensure that the account has the 'Log on as a service' right. Use the Local Security Policy editor (secpol.msc) as described in previous fixes.
5. 5 If using SQL Server, open SQL Server Configuration Manager, go to 'SQL Server Network Configuration', and ensure 'Named Pipes' and 'TCP/IP' are enabled. Also, check the 'Force Encryption' setting; if enabled, ensure certificates are properly configured.
6. 6 Restart the service that is failing. You can do this by opening Services (services.msc), finding the service, right-clicking, and selecting 'Restart'.