How to fix error error-ipsec-mm-auth-in-use in Windows 11

Solution Steps

1. 1 Press Windows key + R, type "secpol.msc" and press Enter. This opens the Local Security Policy editor.
2. 2 Navigate to "IPsec Policies on Local Computer".
3. 3 Right-click on the policy that contains the authentication method you want to change and select "Properties".
4. 4 Go to the "Security Rules" tab. You'll see a list of rules. Identify which rules are using the authentication method you're trying to modify or delete.
5. 5 For each rule that uses the method, either edit the rule to use a different authentication method, or temporarily disable the rule. To edit, select the rule and click "Edit", then change the authentication method in the wizard.
6. 6 If you want to delete the authentication method entirely, you must first ensure no rules reference it. After editing all rules, you can remove the method from the policy's authentication method list (if it's a custom method).
7. 7 After making changes, click OK and run "gpupdate /force" in an admin command prompt.