Nasty macOS flaw is bricking MacBooks: Don't install this update

MacBook Air 2020
(Image credit: Future)

A new macOS update is causing more problems than it fixes, with Mac users reporting a host of nasty problems — including bricked MacBooks.

"The 8 April 2020 Supplemental Update for Catalina 10.15.4 brought the system down for a few hours," said one poster on Apple's own discussion forums

"WARNING macOS Catalina 10.15.4 Supplemental Update BRICKED my 13 inch Macbook 2018!" posted another user on MacRumors' forums.

"This bricked my 2019 MBP. Not providing power to devices either. Needs an SMC reset but won’t accept it," posted a third. "Be afraid, be very afraid. Timing couldn't be more brutal."

Other users reported that the download didn't work at all through the App Store. 

This supplemental update for macOS 10.15.4 Catalina, released Wednesday (April 8), was meant to resolve issues created by the 10.15.4 update in late March. 

That earlier update created issues with systems crashing during large file transfers, failures to wake up from sleep mode, unresponsive USB-C ports, random restarts and even kernel panics.

What to do about the bad macOS Catalina update

The new update may indeed fix those, but it seems to be making things worse. Until Apple sorts this all out, don't install the Supplemental Update for Catalina 10.15.4.

If you have done so and your machine is stuck or otherwise hangs, one poster on Apple's discussions forums might have found a way around the issue. 

"I went to Recovery Mode, ran the Disk Utilities First Aid and then rebooted again," tim01 posted. "My screen came up and I was able to sign in."

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Paul Wagenseil

Paul Wagenseil is a senior editor at Tom's Guide focused on security and privacy. He has also been a dishwasher, fry cook, long-haul driver, code monkey and video editor. He's been rooting around in the information-security space for more than 15 years at FoxNews.com, SecurityNewsDaily, TechNewsDaily and Tom's Guide, has presented talks at the ShmooCon, DerbyCon and BSides Las Vegas hacker conferences, shown up in random TV news spots and even moderated a panel discussion at the CEDIA home-technology conference. You can follow his rants on Twitter at @snd_wagenseil.

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  • kurtschlatzer
    MacBook Pro (Retina, 15-inch, Late 2013, 16mb) - No problems whatsoever with the upgrade.
    Reply
  • sschroeder3932
    Mid 2012 MBP bricked after this update. Called support and they have NO CLUE what is wrong with my computer. Turn off your automatic updates. I am out $1200 and I am a poor student. I am so disappointed.
    Reply
  • sanitycheck
    sschroeder3932 said:
    Mid 2012 MBP bricked after this update. Called support and they have NO CLUE what is wrong with my computer. Turn off your automatic updates. I am out $1200 and I am a poor student. I am so disappointed.

    I have the exact same model as you have, same year, everything. I had a problem with the last update that seemed to brick mine. The solution turned out to be to shut the whole machine off, open it up in back, unplug the battery, leave it unplugged for a minute, plug it back in, reassemble the back panel, and start up again. I was able to login after that.

    I'm holding off on this update for awhile, but I figured my experience might still help you.
    Reply