I've got this problem where the wordpress site will throw up a 404 if the wp-login.php has an ampersand appended after it (e.g. session expired argument).
I've changed themes, disabled all plugins, renamed .htaccess to .htaccess1 and I still get a 404.
It looks like wp-login.php is not linking the "&" after it e.g "wp-login&whatever=blah".
I also have another problem if the "redirect_to" has a colon in it e.g. "redirect_to=http://blah.com/" it will result in a 404 too. If you remove the colon, you just get the login page.
So I suspect both issues are related and its not encoding the url properly? So it sees theses symbols as programing syntax.
I don't code in php so I need some help on what code and where to put it to ensure when WP loads a page it ensures the url its fed is encode properly...
Any help grately appreciated.