Have you recently Upgraded or Changed Skins

no to both
but am curious as to why you are asking

Only because an upgrade is an opportunity for small omissions and oversights.
Also, an older skin wont work with the new versions.

Try upping your memory limit in conf/_advanced.php

¥

Recently a hack I honkered into a phpbb forum I run died. I figured one of the files on my server went belly up and could have looked for it but figured "oh well" and simply deleted it. It was a chat room that I think no one used so no loss.

So back to your issue eh? It is *possible* that you've lost a file on your server. I hope you have backup copies of stuff on your computer because now might be a good time to delete your entire /inc/ folder from your server and upload your backup. And just to be thorough the admin.php file in your root level.

If you don't have a backup check out the bottom of any admin page for your version, then get that version from the download tab above, unzip it, and upload the shiny new copy of the /inc/ folder.

OR one by one by one by one by one by one check out each and every file in each and every folder until you find a file that is (most probably) zero bytes on your server and replace only that file.

No promises this is gonna help ... but it might.