I just experienced this problem on my TbMbp. When you boot into normal mode, it will present you the Network Connection screen to choose a WiFi access point or Ethernet. No matter what you do, it will always fail and leave you with the message where the Mac can't start up unless the critical update is installed. This was performed on a 2016 model 15 inch MBP (flagship model).
Here's what I tried:
- SMC and NVRAM reset
- Online Recovery, First Aid on internal SSD
- Mac Diagnostic Utility (showed no problems)
- Time Machine Backup from an earlier, working point in my backup history
- Delete Partition, reload OS from scratch via Internet Recovery
None of these worked. It will always present you with the description at the top of this posting.
Symptoms:
- Will boot into Safe Boot fine. (This is how I managed to save my files to an external HDD)
- Touchbar will not light up, no way to control brightness, volume, etc. from the touchbar.
What I found on the internet about this problem:
- The Mac's OS and the Touchbar's OS (two separate OS's) are having a problem recognizing each other. The T1 CPU for the Touchbar cannot start up because the Macbook's OS (OS X High Sierra) is unable to "see" the Touchbar.
Solution:
- After chatting with Apple online and trying a few things listed above, I asked to schedule my laptop for service at the nearest Apple Store Genius Bar.
- At the Genius Bar, the tech has never heard of this problem at his location, and connected my TbMbp (Touch bar Macbook Pro) to their in-house diagnostic server, and ran something called "Mac Resource Inspector" (MRI) from an iPad. MRI is some kind of Apple Tech-only diagnostic software which connects to a machine inside the store.
- After 15 minutes, I noticed the Touchbar light up, I could see some of the Touchbar controls show up. The diagnostics did not complete until 5 minutes later where it said it found no problems.
- The tech then restarted my machine but each time performed a NVRAM reset before allowing my computer to continue booting into Normal Mode. I noticed my Touchbar light up before finally showing me the login screen.
Final Thoughts:
- I read that some people had their machines shipped out for servicing or replacement. I can't be sure if the problem I experienced is the exact same thing as everyone else but it appears that the MRI software was able to either reset something or actually loaded something into my machine allowing the problem to go away.
- I would strongly suggest that you schedule an appointment and have the Apple Genius Bar technician run the MRI software on your machine.
I hope this helps.
