If SQL Monitor is configured to authenticate users with Active Directory, and you're locked out of your Active Directory administrator account – for example, if the administrator leaves the company – you need to manually add a new administrator to the SQL Monitor database.

1. In Management Studio, connect to the SQL Server instance that hosts the SQL Monitor database.

2. Paste the following SQL script into a new query window: 

   Script to add new administrator

   INSERT settings.AuthPrincipals
           (Name,
            PrincipalType,
            PrincipalRole,
            [All],
            AuthenticationType
           )
   VALUES  (N'user.name@example.com', 
            1, -- PrincipalType - 1 = User, 2 = Group
            1, -- PrincipalRole - 1 = Administrator, 2 = Standard user
            1  -- All,
            2  -- Active Directory
           )

3. Replace user.name@example.com with the user or group you want to use as the SQL Monitor administrator account. It must be an existing Active Directory user or group.
   If you're adding a group, don't include @example.com.

4. If you're adding a user group, change the PrincipleType value to 2.

   For example:
   

   INSERT settings.AuthPrincipals
           (Name, 
            PrincipalType, 
            PrincipalRole, 
            [All],
            AuthenticationType
           ) 
   VALUES (N'groupname', 
            2, -- PrincipalType - 1 = User, 2 = Group 
            1, -- PrincipalRole - 1 = Administrator, 2 = Standard user 
            1 -- All,
            2  -- Active Directory
           ) 

5. Run the script.