My client is using W3TC with the minify html/xml and when I enable that feature it shows the page that is broken. The page is generated by a plugin that was created for their site, and I have found no errors in the php or apache logs. It doesn’t return any data at all just a blank source. The server is with RackSpace but does not have eAccelerator or any other caching plugin. Any ideas on where to look would be appreciated.
Blank page returned with W3TC Minify HTML/XML
The usual generic approach would be to disable all plugins (except w3tc) and revert to twentytwelve theme and try this way. Then you would turn on one by one (maybe start with a theme) and see if that works.
For specific errors, check if you can increase your log levels: http://php.net/manual/en/errorfunc.configuration.php