My Mac didn't boot after installing a driver, here's how I fixed it.

Two days ago, I installed a Wacom driver on my old MacBook Pro (2014) and found that the machine was no longer booting. It was stuck on the Apple progress bar screen and never entered the user dialog where you usually select your user and enter your password.

Resolving this issue took me three hours. In case you're facing the same problem after you installed a new driver on macOS, I hope this post helps you to fix the issue.

After googling around, I came across a Wacom Forum and Reddit post. Both posts advise booting your Macbook in Recovery Mode (press CMD + R after turning on the Macbook), open the terminal from the Utility menu bar item and delete every file with the word wacom, bamboo or tablet in it.

You can do so by using a combination of the find and rm shell command.

# find all files with the word "wacom"
find / -iname *wacom*

# remove file
rm /some/path/to/a/file

I felt comfortable removing everything wacom or bamboo related, but the search term tablet felt too general. I didn't want to delete important files.

After spending 30min cleaning up countless bamboo and wacom files (it's surprising how many places drivers write files), I rebooted again and ... nothing. The operating system still didn't boot.

Eventually, I came across a Stack Exchange thread. The thread described the stuck loading screen's problem after installing a different driver (something from Roland).

One of the replies mentioned an Extensions directory (/Volumes/Macintosh\ HD/Library/Extensions/). The directory includes files that could block the operating system from booting up. I went back into recovery mode, started the terminal, and inspected the directory.

In my case, the directory included several .kext files (no clue what these do), but looking at the file names, they seem to be related to installed drivers. There was also a directory named tablet ....

Unfortunately, I was dealing with the problem for a while already and entered the try/error state. That's why I missed taking a screenshot of the directory. And I can only say that there was a directory including the word tablet. I had a look into it and found a configuration file that also included the word wacom. I deleted the whole directory, rebooted and saw the success! I was able to sign in again.

Conclusion

I deleted many files related to Wacom and Bamboo across the whole hard drive. Unfortunately, these deletions didn't fix the problem, but luckily they didn't affect the system either. Everything is still running stable after deleting "random files buried in the operating system".

The main reason for the stuck and never disappearing loading screen was the content of the directory /Volumes/Macintosh\ HD/Library/Extensions/.

The next time my Macbook won't boot, that's the first place I'll look for suspicious files!