Custom plugin not seeing custom class

I have a custom toolbar plugin for the editor that I want to search the level for all instances of a custom class. So, in ::PluginButtonClicked() :

for (TObjectIterator itr: itr; ++itr)
{
FMessageDialog::Open(EAppMsgType::Ok, FText::FromString(itr->GetName()));
}

VS2013 claims ACustomActor doesn’t exist when I’ve added it from the editor. I’ve closed the editor, done a full engine+game clean+rebuild, and still errors. If I replace ACustomActor with AActor, everything builds and works as expected. What am I missing to get my plugin class to see ACustomActor?