Same issue in version 1.7.7.2
These are the errors in my console, I can't search for a client either. I don't think your problem will fix mine? I copied the orders folder from my backup because it wasn't there in my folder controllers.
Edit History
These are the errors in my console, I can't search for a client either. I don't think your problem will fix mine? I copied the orders folder from my backup now.