How to save modified DVDPlayback file into /System/Library

Question

How to save modified DVDPlayback file into /System/Library

Hello all!

I have no DVD player anymore in my Laptop (17 inch MBP, 2011). But after every major update the DVDplayer starts with the error: "There was an initiation error - A valid DVD drive could not be found - error -70012" and refuses to open the DVD on a external Drive.

To "repair" this error you have to edit the file /System/Library/Frameworks/DVDPlayback.framework/Versions/A/DVDPlayback and replace the text "internal" with "external" or in hex "496E7465726E616C" with "45787465726E616C"

Ok this is alright. Only I am unable to save the file as before. I opened this file in shell with "sudo"

sudo open -a 0xED /System/Library/Frameworks/DVDPlayback.framework/DVDPlayback

(0xED is the name of the hex-editor)

but I am not allowed to save the file. Also unable to move the saved file from the Desktop into the /System/Library ... to replace the wrong file.

Thank you for your hints!

marek

Posted on Feb 1, 2016 12:24 AM

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Answer 1

Best reply

kjl3000

Level 1

29 points

Aug 19, 2017 1:45 AM in response to Marek Stepanek

These are the steps that worked for me (in sierra 10.12.6):

1. reboot

2. hold cmd-r-s

3. Enter:

csrutil disable; reboot

4. Back in OS X, open terminal, enter:

cd /System/Library/Frameworks/DVDPlayback.framework/Versions/

ls -lO

5. goto Folder: /System/Library/Frameworks/Versions/A

6. open and hexedit (with 0xED for examle) "DVDPlayback"

7. Find & replace „Internal“ to „External“

8. Save

9. reboot

10. hold cmd-r-s

11. Enter:

csrutil enable; reboot

done.

Note: you could also enter terminal in recovery mode to disable System Integriety Protection, but due to a bug terminal is missing in recovery mode in latest sierra releases.

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Answer 2

Feb 1, 2016 1:54 AM in response to Marek Stepanek

Hi Marek,

I used to use this method too, but as i replaced my old macBook over a year ago, i have not done it in recent times.

From memory, you need to changed the Permissions of the file as only the system has read/write permissions.

Try navigating to the file and Control+Click > Get info.

Add your user name to the permissions list and then see if you can edii it.

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Answer 3

Feb 1, 2016 2:09 AM in response to actionmarker

Thank you actionmaker!

I tried the following:

I changed in the Terminal to the desktop, where I saved the changed file before, changed the owner and permissions of this file, and tried to move this file into the original place, to replace it; in the shell the commands look like follows:

cd ~/Desktop

sudo chown root:wheel DVDPlayback

sudo chmod 755 DVDPlayback

sudo mv DVDPlayback /System/Library/Frameworks/DVDPlayback.framework/Versions/A/

But no success! There must be an other trick to correct System files in El Capitain!

Thank you for your help

marek

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Answer 4

Feb 1, 2016 2:48 AM in response to Marek Stepanek

To reply myself and give a possible solution for others:

in Terminal you see the "restricted" Permissions of SIP (System Integrety Protection - since El Capitain) issuing following command; you have to change to the folder first, that means a command like ls -lO /System/Library/Frameworks/DVDPlayback.framework/Versions/ would not work, even with sudo :

cd /System/Library/Frameworks/DVDPlayback.framework/Versions/

ls -lO

drwxr-xr-x 5 root wheel restricted 170 3 Dez 07:35 A/

8 lrwxr-xr-x 1 root wheel restricted 1 21 Dez 05:23 Current@ -> A

To circumvent the SIP you may reboot in recovery mode and entering into the Terminal csrutil disable do what you have to do, and reboot once again in recovery mode and enabling once again SIP with csrutil enable

This is a bit risky - I would not recommend this way. I will try this evening following possibility: Mount my Laptop in Target Modus. Like this the SIP will not be enabled. Make your changes and restart ...

Normally this should work

Best greetings

marek

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Answer 5

dialabrain

Level 10

122,513 points

Feb 1, 2016 2:49 AM in response to Marek Stepanek

I believe you have to disable SiP first, move the file, then re-enable SIP. You can do an online search to find how to disable SiP.

oops, I see you found it. 😁

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Answer 6

Apr 30, 2016 5:48 AM in response to Marek Stepanek

Hi Marek.

It would be great if you could post your solution from beginning to end, if you solved this.

I replaced my internal drive on my Macbook and, as with you, this little hack used to work. Now I am out of my range.

Thank you.

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