Is your Mac’s firmware up to date? It’s simple to check: use the About This Mac command in the Apple menu, click on System Report… and, in System Information, read what it reports for System Firmware Version (in the Hardware Overview). Of course that only tells you what version is installed, and not what it should be.

The other half of the information you need is something which Apple paradoxically doesn’t provide, a list of current firmware versions by model. If your Mac is running Mojave or later, then look here for recent Macs, or here for older ones.

Simpler still, download and use my free utility SilentKnight, which does all the work for you, automatically checking the firmware version against my online database, as well as checking that your Mac’s security data files are up to date, and more.

Quite a few users have had a shock when they’ve checked their Mac’s firmware, which turns out to be ancient, even though they’ve kept macOS up to date. This is most frequent with specific models, such as the iMac Retina 5K 27-inch Late 2015 (iMac17,1), and can occur with other models when their internal storage has been replaced from the original. So what can you then do to update your Mac’s firmware?

If you still have its original Apple-supplied internal disk, replacing that and installing a current version of macOS, perhaps to an external disk, should update its firmware to that supplied with the version of macOS you install. Unfortunately, some have found that they have to repeat this in order to keep their firmware up to date, but others have only had to do it once, and that has enabled subsequent updates to install correctly. If you don’t have its original storage, it may be possible to substitute a SATA disk or similar which has the same effect.

The biggest problem is for the iMac17,1, where many with Apple-supplied internal storage can’t update firmware beyond 170.0.0.0.0, which was current until Catalina was released in October 2019. Those iMac17,1 computers affected seem to have original Apple SSDs, which were an expensive option at the time.

The good news is that Apple now seems prepared, on an individual basis, to fix this problem free of charge. Because this isn’t yet recognised as a more general problem, to get your iMac17,1 fixed you’ll have to negotiate your way through the barriers of Apple Support. Be prepared to be told some surprising stories as to why your Mac isn’t running the current firmware version. These include:

• Version 170.0.0.0.0 is the latest version. It’s not, and hasn’t been since October 2019. Call this out as a straight lie.
• Your Mac is running the latest version, as it doesn’t need anything more recent than 170.0.0.0.0. This too is an outright lie, as Apple has released more than four updates since that version, which apply to all iMac17,1 computers including yours.
• It doesn’t make any difference. This is another lie: of course it does. Why else would Apple have spent the money developing and releasing all those newer versions of the firmware for your Mac?
• Your iMac17,1 can’t have its firmware updated. It can, it just requires Apple to dip its hand into its bulging pocket to fix it, and that’s what Apple Support is there to enable.
• It’s your fault because you’ve installed a memory upgrade or done something else. Surprisingly, those appear irrelevant here, it’s the internal storage which determines success or failure. In any case, where does Apple say that upgrading your hardware prevents firmware from being updated?
• There’s no known problem with updating firmware in the iMac17,1. Of course there is, and you can read a whole series of articles and plenty of comments here (search for iMac17,1) and elsewhere. It has been officially reported to Apple in Feedback entry FB7644127 dated 29 March 2020 too.

You’ll need to persist with your cause so that it escalates until senior support staff reluctantly agree to do something about this. If you have a consumer organisation which can provide assistance, or even a lawyer, then you may find that helps. I explain some of the background in this article.

It’s worth the effort too. Firmware updates are an essential part of your Mac’s security, improve its stability, and ensure that your Mac works properly with recent versions of macOS. It’s disgraceful that Apple, knowing of the problem, seems to be doing its utmost to prevent users from getting it fixed. Worst of all is that affected iMac17,1 computers were among the most expensive Mac models at the time, but now seem to be receiving the least support.