This feature is available for Intel-based Macintosh systems only. Although the emergency tool would work very well on Macs with Apple Silicon, the security design of such Macs won’t allow that third-party applications can be started in the recovery operating system.
Under critical circumstances, your installation of macOS could be damaged by a disk drive failure or by a third-party application which used administrative permissions in such a way that the operating system is no longer starting correctly or does not start at all. When you cannot work with the operating system any longer, utility programs like TinkerTool System also can no longer be of any help to resolve this problem.
Similarly, macOS might still be running, but an important system component which is needed by TinkerTool System could be damaged. Even if TinkerTool System is capable of repairing this failing component during normal operation, this will not help in this particular case, because you might not be able to launch TinkerTool System due to the damage.
However, TinkerTool System offers a solution which can help you even in those two critical cases. The application contains a mini version which can be launched in the special recovery operating system of macOS. The recovery operating system is installed as an addition to each standard operating system into an “indestructible” disk image. It should always launch, even in emergency situations. The small standalone version of TinkerTool System is called TinkerTool System for Recovery Mode, or abbreviated ttsfrm.
Note that you should inform yourself beforehand, before a critical problem occurs, how to launch TinkerTool System in Recovery Mode. You will then be prepared for an emergency. The respective instructions can be printed.
To print the instructions how to launch TinkerTool System for Recovery Mode, perform the following steps:
TinkerTool System will automatically adjust the output to the paper size of your printer.
In case you have printed this reference manual of TinkerTool System, the short instructions to launch the emergency tool are included here as well. Please note however, that the specific start command to launch the program can be different on each Mac, depending on where you copied TinkerTool System.
Turn on your Mac and immediately press and hold the keys ⌘ + R until the Apple logo appears.
If your Mac is protected by FileVault or by a security processor, you will see a password request after a while. Enter the requested password and continue. (This step is automatically skipped for unprotected Macs.)
The window macOS Utilities opens. Use it to start Disk Utility and ensure your operating system volume is mounted. If not, mount it, which can require to enter a passphrase for decryption. Note that there are three different visible volumes for the operating system, by default called Macintosh HD, com.apple.os.update-…, and Macintosh HD - Data. All three volumes should be active after unlocking the decryption.
Quit Disk Utility and start Terminal via the menu Utilities.
Enter the following command, including the quotation marks and with correct capitalization, pressing the return key at the end.
… at this location, the individual command valid for your specific computer should be noted (see window) …
As mentioned already, the command can be different depending on the location of the program and the names of your volumes, folder, and application. It could be, for example:
"/Volumes/Macintosh HD - Data/Applications/TinkerTool System.app/ Contents/SharedSupport/ttsfrm.app/Contents/MacOS/ttsfrm"
The actual call that must be typed as one single line into the Terminal window to launch the application, can be reconstructed as follows:
This means the pattern of the call is
where all parts within angular brackets must be replaced by the actual names that are established on your computer. Don’t omit the quotation marks and don’t replace them by typographical variants. Press the return key only at the end, even if the command above is written in multiple lines for reasons of space.
If you have multiple disk volumes on your Mac or even multiple operating systems are installed, there will be restrictions which volumes will later be accessible in Recovery Mode and which operating system can be repaired. The following basic rule applies:
TinkerTool System for Recovery Mode only works on the volume group and its associated operating system where the application itself has been stored.
This results in the following consequences:
A volume group for macOS consists of the system volume, its associated snapshot update volume, and its data volume. You can review the details of this grouping via the pane APFS.
TinkerTool System for Recovery Mode can only be used after the recovery operating system of macOS has been started. Detailed information on this topic can be found in the chapter Working in macOS Recovery Mode.
Older variants of TinkerTool System had been shipped with a different type of emergency tool which was designed for the Single User Mode of macOS. This program had to be installed expressly in a separate step. Apple no longer supports Single User Mode of macOS officially and many Macs are now pre-configured by default to prohibit Single User Mode for security reasons. This has made the old version obsolete, so it should be removed. TinkerTool System detects automatically whether an outdated version of the previous software is available in the running operating system. It will shows this at the bottom of the Emergency Tool pane. In this case, simply click the button Remove legacy tool and follow the application’s instructions to clean your Mac.