How to fix domain redirect?

What "site optimizer"?

Also, the reason you are getting part of that (the ;wwwRedirect) is because you accessed the site from matrix13.com while you have indicated that your site URL is www,matrix13.com in your forum settings...

You should either put an htaccess redirect/rewrite that automatically bounces users to the www address -- or change your settings and put a redirect/rewrite that automatically bounces users to the non-www address.

However you are always going to have issues with external caches, since the system adds the session ID to non-signed in users' URLs.