I run the latest version of wp and w3c, and whenever I activate a plugin wp admin pages just show blank, then if I disable w3c I can activate any plugin, but then if I activate w3c again, I get blank pages again. It seems w3c doesn't like some plugins.
1) With w3c activated, I activate All-in-One SEO -- Blank admin pages
2) With w3c deactivated, I activate All-in-One SEO -- No problem, but if I activate w3c afterwards, I get blank admin pages.
Ehh, what the heck? I have tried with several other plugins, they give the same result.