Got "APP is not verified" Error on Macs Joshua Chang October 15, 2018 03:41 Go to https://www.tiertime.com/downloads/software/, find the LKD File for MAC V x.x.x.x. Open UP Studio, choose Activate, and then load the LKD file. Related articles Why Mac Vers.2.4 UP Studio Show "Please Activate" all the time? How to activate the printer Installation Failure - an error occurred during installation and progress bar rolling back Chapter 1. Cetus MKIII 3D Printer Parts Introduction How to solve non-Administrator users cannot operate the software in a domain/school network? Comments 0 comments Please sign in to leave a comment.