I'm just getting blank empty pages back from my YAF!
The last thing I did, logged in as admin, was ban and kill a suspicious user, then YAF died - it appears that any page with the YAF:Forum control just returns nothing.
I tries clearing yaf_active and yaf_activeaccess tables. There are no obvious file changes or corruptions on the server. I've restarted the app pool. The upgrade wizard runs fine, as does the rest of the website.
What can I check next?