Can't boot after WACOM install (my fault; I know)

[JordanOrlando]

I've been running Sierra perfectly since 2017, with a fairly robust system (many drives; devices etc.). All working perfectly. (I can supply the details of my CLOVER install; EFI details if necessary).

Motherboard — ASUS P9X79 WS
CPU — Intel Core i7-3930K @ 3.20GHz
Graphics — NVIDIA GeForce GTX 970

Yesterday I (probably stupidly) installed the Sierra-specific Wacom driver for a new Cintiq tablet (screen via HDMI; tablet via USB; all connections via Cintiq hub). The install ran and then forced a reboot.

When it came back up, it still worked perfectly and the tablet worked pretty well — initially it came alive as a third monitor and then I lost that function (I assume it's just a problem with settings, etc.)

But upon a second reboot, the machine won't boot. I get "Reboot and Select proper Boot device"/"or Instert Boot Media in selected Boot device and press a key_"

I moved the boot drive to another mac and used its Finder to remove the new "AppleMobileDevice.kext" and replace "prelinked kernel" from a very recent Time Machine backup (since these were the two files that got modified/added circa the Wacom installation). I also removed everything in ~/Library/ (the user Library) that said "wacom" — all of which was installed at that same point. No dice.

Is there a way I can get out of this, without having to start from scratch?

Thanks in advance for any advice or assistance.

Apologies if this is the wrong forum for this.

 

[UtterDisbelief]

I've been running Sierra perfectly since 2017, with a fairly robust system (many drives; devices etc.). All working perfectly. (I can supply the details of my CLOVER install; EFI details if necessary).

Motherboard — ASUS P9X79 WS
CPU — Intel Core i7-3930K @ 3.20GHz
Graphics — NVIDIA GeForce GTX 970

Yesterday I (probably stupidly) installed the Sierra-specific Wacom driver for a new Cintiq tablet (screen via HDMI; tablet via USB; all connections via Cintiq hub). The install ran and then forced a reboot.

When it came back up, it still worked perfectly and the tablet worked pretty well — initially it came alive as a third monitor and then I lost that function (I assume it's just a problem with settings, etc.)

But upon a second reboot, the machine won't boot. I get "Reboot and Select proper Boot device"/"or Instert Boot Media in selected Boot device and press a key_"

I moved the boot drive to another mac and used its Finder to remove the new "AppleMobileDevice.kext" and replace "prelinked kernel" from a very recent Time Machine backup (since these were the two files that got modified/added circa the Wacom installation). I also removed everything in ~/Library/ (the user Library) that said "wacom" — all of which was installed at that same point. No dice.

Is there a way I can get out of this, without having to start from scratch?

Thanks in advance for any advice or assistance.

Apologies if this is the wrong forum for this.

Hi there.

1) When you delete or change a kext of any type that is not in the EFI folder, you need to rebuild the 'kext caches'. There are utilities that do this or you can use Terminal commands.

If you don't do this then though you may have changed something, the file access permissions will be wrong and the kext will have been 'cached' anyway and still in use.

2) The fact that your PC would no-longer boot at all suggests that something else has gone wrong with the macOS EFI folder on your main drive. Do you have Windows installed on the same machine as well?

 

[JordanOrlando]

Hi there.

1) When you delete or change a kext of any type that is not in the EFI folder, you need to rebuild the 'kext caches'. There are utilities that do this or you can use Terminal commands.

If you don't do this then though you may have changed something, the file access permissions will be wrong and the kext will have been 'cached' anyway and still in use.

2) The fact that your PC would no-longer boot at all suggests that something else has gone wrong with the macOS EFI folder on your main drive. Do you have Windows installed on the same machine as well?

Thanks for responding!

Your point #2 seems important (and had occurred to me), since generally when there's a problem I'll get at least to the clover screen, rather than to that puzzled message.

My logic was that the Wacom driver installer would mess with the Mac System but not with the EFI folder (since the EFI folder is invisible to Mac OS, right?) (and anyway why would a simple tablet driver need to mess with the EFI).

It's possible that some entirely unrelated other issue, occuring the same day, messed up my boot drive and I'm completely on a wild goose chase with the WACOM stuff.

I do not have Windows installed.

 

[JordanOrlando]

Thanks for responding!

Your point #2 seems important (and had occurred to me), since generally when there's a problem I'll get at least to the clover screen, rather than to that puzzled message.

My logic was that the Wacom driver installer would mess with the Mac System but not with the EFI folder (since the EFI folder is invisible to Mac OS, right?) (and anyway why would a simple tablet driver need to mess with the EFI).

It's possible that some entirely unrelated other issue, occuring the same day, messed up my boot drive and I'm completely on a wild goose chase with the WACOM stuff.

I do not have Windows installed.

Can I replace the EFI folder with a copy of the previous working one?

(Using Clover Configurator on another mac, having moved the boot drive over.)

 

[JordanOrlando]

Hi there.

1) When you delete or change a kext of any type that is not in the EFI folder, you need to rebuild the 'kext caches'. There are utilities that do this or you can use Terminal commands.

If you don't do this then though you may have changed something, the file access permissions will be wrong and the kext will have been 'cached' anyway and still in use.

2) The fact that your PC would no-longer boot at all suggests that something else has gone wrong with the macOS EFI folder on your main drive. Do you have Windows installed on the same machine as well?

You're a genius!

I looked through the EFI partition of my boot drive for anything with a recent modification date, and saw that EFI/APPLE/EXTENSIONS/FIRMWARE.SCAP was from two days ago (while everything else was from 2017 -- when I built my machine -- or earlier). So I just replaced that with a backup, and now the system boots perfectly!

Thank you very much indeed for your help!

Regards,
Jordan

 

[UtterDisbelief]

Can I replace the EFI folder with a copy of the previous working one?

(Using Clover Configurator on another mac, having moved the boot drive over.)

If it's for the same hardware, sure.