CMS Made Simple Forums

I've had the Frontend User and CustomContent modules running on a site for the last year without a hitch, and then out of nowhere it's stopped working.  When I try to view the root URL of the site, rather than being redirected to the Frontend login page, I just see a 'File Not Found' page.  Any idea what might be wrong?

I'm running 1.0.4 CMSMS, 1.1.2 Frontend User, and 1.4.4 Custom Content.

It's unlikely that it's an FEU/customcontent problem.

Probably something much simpler, like either your login page alias has changed, or the code that does the redirecting got changed somehow and it's now trying to redirect to a page that doesn't exist.

Thats where I'd look.