403 Forbidden on when posting HTML chars after server move

The site I'm working on was working perfectly on a development server, however the client has his own server so I transferred the files + database, sorted file permissions etc.

Now everything on the site works fine however when I send certain HTML characters via post (from WYSIWYG or regular textfield) e.g. <h1> or <ul> I get a Forbidden 403 Error - You don't have permission to access [THE-REQUESTED-URI] on this server.

It's a LAMP Server, PHP 5.3

By the way Apache mod_security isn't running. What else could be causing the problem??

Also there is开发者_JS百科 nothing in the servers error log about this.

Add enctype="text/plain" to your form tag. It might help.