php forum outputs string of text, how to find source of said string? : <p>I'm working on a site which is a simple php forum, and every so often it'll insert an alert/error div on the page, e.g., "Error! You can't do that because of this," or whatever.</p>

<p>How do I search each of the files on my server for the string "Error! You can't do that because of this"? Asked differently, how do I find the source of the various errors when they arise, you know, without having to manually look at every single .php file on the server; thanks.</p>
