Jimmy Bergmark from JTB World, has reported that the just released SP1 for AutoCAD 2017 breaks the functionality of the "plug-in auto loader mechanism". Please make note of this before installing SP1, which is currently only available via the Autodesk Desktop App. References below:

Ref 1: AutoCAD 2017 Service Pack 1 and a word of warning
Ref 2: AutoCAD 2017 Service Pack 1 is out but you probably don’t want to install it