My hosting service, Dreamhost, announced they would be upgrading every one off PHP4. Only people using old software would get bitten. I’ve kept my software current, so I wasn’t worried.

Only this of all eight domains started showing an HTTP 500 error (Internal Server Error). I dreaded having to go through and determine why. Turns out it was easier than I thought…. In Dreamhost’s panel, the domain was still configured to use PHP4. When I changed it to use PHP5, the WordPress started working again.

I would have thought part of an upgrade would be to change this configuration. At least it was just a simple change and not digging through code and logs.