Ah, the classic Codeigniter white screen of death. I ran into this the first time I used CI. Unbelievably frustrating that such a popular framework could cause something like this with no error output.
In my particular case, it was because I attempted to use the Database class with MySQLi, but my target environment didn't have the MySQLi module installed. For some reason, CI suppressed all the usual error output, so it turned a 2-minute investigation into a 2-hour investigation.
So that being said, I'd check the following things:
- error_reporting set to
E_ALL
in your php.ini, and display_errors is on.
- Turn on log_errors as well.
- Check that the classes you're using don't rely on a special PHP module that you might not have
If you can't find anything with error output, you're going to have to dig deeper. If you have xdebug installed, I'd highly suggest using that... surround your code in a trace and see where it's choking.
I ended up having to find the cause of my WSOD by drilling down through the framework classes itself and dumping output (no xdebug was available). It's not fun, but it eventually worked.