You need to load your website, then look at the GENERATED HTML. Then look at line 184 of that HTML.

That will show you the broken href.

when you know what is broken, you can call up the file that generated that piece of html.

index.php is NOT at fault... some other file is at fault - probably one that is manually edited such as an EZPage or a DEFINED PAGE.

Do NOT mess about with index.php ... it has nothing to do with the problem you are experiencing.