This is a follow-up question to Mac Pro 4,1 (Early 2009) Sierra Compatibility?

I installed macOS Sierra on an early 2009 Mac Pro and now I noticed that my wifi hardware "is not detected". Here's what I did:

  1. I used the MacPro Firmware updater to change it's version from 4,1...5,1.

  2. I installed a 480GB Mercury Electra 3G SSD which I bought from OWC in the next available slot.

  3. I installed Sierra Public beta. It's been updated twice, and now it's at 10.12 Beta (16A313a)

  4. I now noticed that the wifi icon in the toolbar has a big X on it, and it says that no wifi

Is it possible that there's a new incompatibility with the wifi card with Sierra, or that somehow adding the new SSD caused a problem?

Does anyone have experience with this and/or have any hints?

  • My educated guess is you would need to replace the existing WiFi card with a newer BT LE card - link to first ad for one I could find. I have one of those in my upgraded 4/5,1 but haven't tried the Sierra beta yet, so I can't say for certain, but it does look like Apple are dropping support for older WiFi cards. I'm sure it's related to the Continuity issue - Guide
    – Tetsujin
    Sep 1, 2016 at 16:24
  • Sorry, linked to wrong card - osxwifi.com/…
    – Tetsujin
    Sep 1, 2016 at 16:31
  • But the machine worked fine with El Cap. That link implies that is needed for Yosemite. Which I ran, and El Cap, without any wifi issue.
    – pitosalas
    Sep 2, 2016 at 0:11
  • Try to reinstall OS X EI Captan Sep 2, 2016 at 0:27
  • Just tested, running latest Sierra public beta on a machine with the newer WiFi/BT card - working correctly [though not at first boot, it's been recognised successfully subsequently]. I updated my card as soon as I got the machine, so I've never really used it with the older one, & it's a job you wouldn't want to tackle twice, just to test - very fiddly.
    – Tetsujin
    Sep 2, 2016 at 11:14

3 Answers 3


Apple decided to try and piss off as many educational customers as possible by not including basic broadcom drivers from their AirPort wifi cards. Even the later 4321 cards do not have a driver in MacOS Sierra and some of them shipped with Mac PRO 2010's. So Apple even lied to their own owners about what models would be supported. I have two Mac Pro's one is a 2009 and the other is a late 2010. The late 2010's wifi does work. The original card from the 2009 does not work and the upgraded BCM94321MC also does not have a driver in Sierra. My 2nd Mac Pro has the following Wifi that does work. Apple Airport Extreme BCM94322MC. Comedic isn't it the BCM94322MC works and the BCM94321MC doesn't. I ordered a second 22 to fix this issue.

  • Sounds very plausible. So to be clear: you had the same problem I reported, you purchased and installed Apple Airport Extreme BCM94322MC, and the problem resolved itself. Did you (could you, should you) uninstall the old Wifi card?
    – pitosalas
    Sep 25, 2016 at 23:42

Just an fyi, the BCM94321MC is not an updated card. That card has been around since at least 2006/2007 as it is the same card that shipped in the original (silver) Apple TV.


It maybe an issue with the new software. Downgrade from Sierra to EI Captain. There is a guide here.

  • Yes I had that guess too. As is indicated in my question.
    – pitosalas
    Sep 2, 2016 at 13:56

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .