Could not find engine!

Could not find engine! The error occurred while installing the eSellerate engine. 0XE001004

This error (and similar) generally means that something went wrong with the original installation and a required component of eSellerate (our licensing and activation provider) didn't install properly. Please download and install the eSellerate Engine Update and try activating again.

If this doesn't work (macOS-only), try deleting the /Library/Frameworks/EWSMac.framework and /Library/Frameworks/EWSMac-GC.framework folders, and then install the eSellerate Engine Update again.