I was getting the dreaded white page of death and I think it is down to the Redirection plugin (I deduced this by selectively disabling and enabling each plugin until the site came back up again).
I am using Redirection 2.2.9 on WordPress 3.2.1 and the other plugins I am using are:
Broken Link Checker 1.3
CSS And Script File Aggregation 1.3.1
Google Analytics for WordPress 4.1.3
Google XML Sitemaps 3.2.5
Grunion Contact Form 2.2
Hide Trackbacks 1.0
Highslide for WordPress *reloaded* 1.22
NextGEN Gallery 1.8.2
Post Type Switcher 0.3
Uploads Folder 2.0.2
Widget Logic 0.48
WordPress SEO 0.4.2
I found some threads that suggested turning off the automatic creation of redirects for modified posts but after doing this, the problem persists. I deleted the redirects in the modified posts group and then deleted the group itself but again, the problem still persists.
Can anyone advise what I can try next?