What you need to know

  • There are some reports that updating to Catalina is causing bricking with some Macs
  • The issue seems to be a result of an EFI firmware update.
  • Initial reports suggest the issue is only affecting a very small number of devices.

A report via 9to5Mac suggests that a very small number of Mac users may be experiencing bricking when updating to macOS Catalina.

According to the report:

There are forum reports of the update to macOS Catalina resulting in some Macs becoming non-responsive, with some indication that an update to the EFI firmware may be responsible … There are multiple threads on Apple's support forums, with most reports appearing similar in nature.

Many of the reports seem to concern older Macs from 2014 and 2015. All the reports tell the same story of upgrading to Catalina, only to be greeted by Apple's black screen and the "?folder" icon. One user reported that an unofficial service center directly programmed the EFI with a special tool, which fixed the problem. This would seem to confirm the suggestion from several of the reports that corruption of the EFI firmware may be to blame.

At this stage, there are a very small number of reports, so whilst it no doubt seems to be an issue, the scale of the problem seems to be very limited at this juncture.