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Ask iteachmac Your Own Question

iteachmac, The Duke!
Category: Mac
Satisfied Customers: 865
Experience:  Mac help ,music midi expert, logic pro recording ,electrical installation ,ilife & all mac computing
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Hello! I have a mac pro 8-core, and I have been running

Customer Question


I have a mac pro 8-core, and I have been running "Logic" music software just fine.

So next, I get a prompt that there is a software update ready for download. I pull it down, and NOW LOGIC DOES NOT WORK!!!! please help!!:(?:(:(:(:(:("(:"(

The message I get when I try and launch Logic is:


The update I pulled down was:

"Firmware 1.4 mac pro EFI"

I'm sooo lost:( Any help would be so appreciated.

Thank you,
[email protected]
or [email protected]
Submitted: 6 years ago.
Category: Mac
Expert:  iteachmac replied 6 years ago.
Hi ,

I have found a way to fix this "coreFoundationUnknownErr" error with Logic .

First you remove these files:

/Library/Application Support/ProApps/Logic Studio System ID
/Library/Application Support/ProApps/ProAppsSystemID

Then launch your Logic 9.0.2 FIRST, enter your serial and continue.

Open a song and make sure it all works.

Quit and then launch Logic 9.1.
Should work perfectly after that.

This should work in 10.5.8 Leopard.

This seems to only work if you launch 9.0.2 first if you still have both application version installed on your Mac .

Hi , i think what has happened is that the Firm ware update has changed the config of the Mac .

Basically the Logic software thinks the Mac is now a different Computer Model hardware and is stopping the Application from running with the error ,
this is my thinking of what is occurring .

Removing the files as outlined above should , on reinstall of the Application need your serials and code to be reentered , this will regenerate the files you have trashed with the new machine ID / firmware .

hope this helps :)

There is also an option within the Finder for the "Logic application" depending on OS version . Use get info on the logic application to find settings for running Logic either 32bit or 64bit mode , and may help also .

Customer: replied 6 years ago.

Hey there,

I'm so sorry I have not replied yet.

I REALLY appreciate your response!! It seems very plausable.

The only problem is that I am sooo not a tech guy, so when you say "remove this file, or that file", i'm TOTALLY lost.

Is there any way your answer can be idiot-proofed a bit?

Thanks again very much.

Darryl Swann
Expert:  iteachmac replied 6 years ago.
a: Ok , :)

First you remove the files , place them in the trash :-

1 Open your Mac HD disk .

2 Open the library folder , inside you'll find the "Application Support" folder .

3 Open the "Application Support" folder .

4 Open the "ProApps" folder .

5 You should see the files now . "Logic Studio System ID" & "ProAppsSystemID".

6 Drag both files to the "Trash" in the lower Dock , on the far right hand side.

7 Then launch your Logic 9.0.2 FIRST, enter your serial and continue.
Logic should be in the Applications folder of your Mac HD .

8 Open a song and make sure it all works.

9 Quit Logic.

10 Launch Logic version 9.1.

11 Hopefully it will work after that.

12 Thanks .

13 Let me know how you get on.

14 :)
Customer: replied 6 years ago.

Dude, you're the MAN!.

I'm gonna try this right now. Ok to hit you back if I run into a snag? Looks pretty stupid-proof:)

Much appreciated.

Did you receive the $13 I pledged?

Customer: replied 6 years ago.

Hey Duke,

Sorry to say that didn't work. Bummer.

I found the files you said to find per your very clear instructions and threw the files away.

But I still got that same dumb error when I tried to launch Logic.

I only have the first version of Logic 9. Not 9.1.

I'm gonna try some other things, but if you have any other suggestions, please send if you have time.

Thanks again man,


Expert:  iteachmac replied 6 years ago.
Hi ,
Did it ask for you to register again once it loaded up ?

have your tried updating the Logic app ?

Use Apple menu , Software update .

Update all software , Logic should be updated to the latest version.

Let me know what OS your running ? Apple menu , About this Mac ,
before you update.

I can send a better combo update if you need it .

lets see.?

Thanks .