Change thread order for existing members?

[vestaviascott]

I have managed to set the default thread order for for new registrations. How do I change it for existing members?

I found an older thread that referenced this: Maintenance > Execute SQL Query > Automatic Query -> Posts - Newest First


However, when I click on Execute SQL Query, I get this message:

You are not authorized to execute SQL queries


And I'm the forum ADMIN!

Please help :-)