TECH SUPPORT & TECHSPLANATIONS

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Make sure you check out these important support articles on Apple’s website to better understand the latest features.

MOVING FROM A WINDOWS PC TO MAC?

Windows Migration Assistant can help you move from a Windows PC to a Mac, transferring your photos, documents, email accounts, and more. Here’s what you need to know to do it: bit.ly/ml176ask1.

BACKUP DISKS WITH TIME MACHINE

Want to know which types of external storage device you can use to make a Time Machine backup? This Support article shows you all that are available: bit.ly/ml176ask2.

SAFELY OPEN APPS ON YOUR MAC

Gatekeeper ensures only trusted software can run on your Mac. If you get a pop–up message after installing apps outside of the App Store, here’s what you need to know: bit.ly/ml176ask3.

> What does upgrading macOS to Big Sur mean for my firmware?

When I upgrade my Mac to Big Sur, I gather it will get a firmware update. Will it still be able to run Mojave, or will I have to downgrade its firmware before it can do that?

All Macs upgrading to macOS 11 Big Sur should expect a firmware update, which should extend in matching Security Updates to other supported versions, Catalina and Mojave.

Because firmware is installed into the logic board, each Mac can only run one version: you can’t switch between versions to start up in a different release of macOS. As Macs can’t ordinarily downgrade firmware, only upgrade, if you want to run both Big Sur and Mojave on the same system, your Mac has to run the newer firmware anyway. So long as the versions of macOS are reasonably close together, that normally works fine, and is supported by any necessary changes in the kernel and other components supplied in a Security Update, for instance.

This becomes more tenuous when the two versions are further apart. Running a version of macOS which hasn’t been supported for some years, such as Sierra, with Big Sur firmware poses more risk of incompatibilities appearing. Other issues, such as changes in the APFS file system, are more likely to cause problems, and are addressed by running an older macOS in a virtual machine.

New firmware installed when upgrading your Mac to Big Sur should remain compatible with at least the last two versions of macOS.

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