the bless of the installer disk failed.

3 min read 01-10-2024

When attempting to install or upgrade macOS, you may encounter the error message: "The bless of the installer disk failed." This issue can be frustrating, especially when you're eager to start using the latest features or improvements from Apple. In this article, we’ll explore the causes of this error, provide some solutions, and offer additional insights to help you successfully install macOS.

Understanding the Error

What Does "The Bless of the Installer Disk Failed" Mean?

This error typically indicates that the system was unable to properly configure the installer disk (usually a USB drive) to be bootable. When you attempt to install macOS, the system needs to "bless" the installer disk, which is a process that prepares the disk to be recognized as a valid startup disk. If this process fails, you will not be able to complete the installation.

Common Causes

Corrupted Installer: The macOS installer might be corrupted or incomplete.
Improperly Created Bootable USB: The USB drive may not have been created properly.
Incompatible Hardware: Some older Macs may struggle with newer operating systems or installers.
Disk Errors: There could be issues with the USB drive or the drive onto which you are installing macOS.

Solutions to the Error

1. Verify the macOS Installer

Solution: Re-download the installer from the Mac App Store to ensure you have a complete and up-to-date version.

Example: If you're trying to install macOS Monterey, make sure to download it directly from the App Store and check its integrity.

2. Create a Bootable USB Drive Properly

Solution: Use Terminal to create a bootable USB drive correctly. Follow these steps:

Insert your USB drive (ensure it has at least 16GB of free space).

Open Terminal and use the following command:

sudo /Applications/Install\ macOS\ Monterey.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

Replace MyVolume with the name of your USB drive.

Press Enter, and follow the prompts.

Important Note: Ensure the USB drive is formatted as Mac OS Extended (Journaled) using Disk Utility before running the command.

3. Check Disk Utility for Errors

Solution: Use Disk Utility to check for any errors on your USB drive and the destination drive.

Example:

Open Disk Utility from Applications > Utilities.
Select the drive in the sidebar, and click First Aid.
Follow the instructions to repair any detected issues.

4. Try a Different USB Port or Drive

Solution: Sometimes, the problem may lie with the USB port or the drive itself.

Example: If you are using a USB 3.0 drive, try switching to a USB 2.0 port or using a different USB drive altogether.

5. Reset NVRAM and SMC

Solution: Resetting the NVRAM (Non-Volatile Random Access Memory) and SMC (System Management Controller) can sometimes resolve boot issues.

Steps to Reset NVRAM:

Shut down your Mac.
Turn it on and immediately press and hold Option + Command + P + R for about 20 seconds.
Release the keys after the second startup sound.

Steps to Reset SMC:

For MacBook with T2 Security Chip: Shut down your Mac, press and hold Control + Option + Shift for 7 seconds, then press and hold the power button. Hold for another 7 seconds and release.

Conclusion

Experiencing the "The bless of the installer disk failed" error can be a roadblock in your macOS installation journey. However, by following the steps outlined in this article, you can resolve the issue and successfully install your desired macOS version.

Additional Tips

Always back up your data before performing installations or upgrades.
If you continue to encounter issues, consider seeking assistance from Apple Support or the Apple Community forums.

This troubleshooting guide aims to provide clarity and actionable steps to address the installer disk error. By understanding the causes and implementing the recommended solutions, you can enhance your experience with macOS installations.

References

Original Questions and Answers sourced from GitHub discussions on macOS installation issues. Proper attribution is given to the community for their contributions.

By integrating insights from GitHub with practical solutions and additional analyses, this article is designed to be informative and helpful for readers facing the same installation hurdles.