I've inherited a website with a problem! Basically the site runs pommo mailing list, which has worked fine for years. Recently though the website domain changed. Since then - or at least at a similar time - pommo has just stopped working completely. It does nothing but outputs blank pages.
I've never done any php development so I've no idea where to start in terms of debugging this. I've checked that the files etc all exist on the server: they do. I've uploaded a test html page which works. I've uploaded a test php page containing: <?php phpinfo( ); ?> and it works. But when I visit any pommo php page, the browser just renders a totally empty white page - no source HTML at all, just nothing!
Can anyone suggest how to debug this? Even an error message would be somewhere to start.