White Screen of Death
 

I get it. Basically, it's times when the PHP just fails and no HTML whatsoever is outputted. You get a white screen without a title or source code. I have experienced this on exactly two forums: my own and another forum that also runs on vBulletin. What is the cause and how can I prevent it?

Here is a page from the manual about troubleshooting blank or 'white' pages: http://www.vbulletin.com/docs/html/blank_pages

When I get a white page, the first thing I do is look in the error_log. (If you don't know where those are, ask your host.)

Incidentally, do you run vBSEO? This could cause it too.