"After upgrading to macOS Mojave 10.14, my MacBook Pro won't boot at all. I have run First Aid in macOS Recovery mode, but it failed on the startup disk. Then I chose to reinstall macOS directly, but it didn't allow me to do that and gave me this error message: “You cannot upgrade this version of macOS because a new version is installed”. Anyone can help me?"
Some users report that their MacBooks, iMacs and other Macs will not start after macOS update to macOS Mojave and hangs on a gray screen with an Apple Logo. Just like what happened above, if Mac won't reinstall Mojave in macOS Recovery mode, you may receive an error message: "You cannot upgrade this version of macOS because a new version is installed". This passage will explain why this error happens and how to fix it.
Why does 'You cannot upgrade this version of macOS because a new version is installed' error occur?
This is because when you install an operating system, your Mac computer will store an installation image in macOS Recovery mode which you can use to run diagnostics and re-installations. The boot image in macOS Recovery mode keeps unchanged after OS update. So when upgrading to a newer OS, the installation image in macOS Recovery mode is always lower than the OS we are using.
However, Mac will refuse to repair or reinstall the newer OS with the older installation image in macOS Recovery mode and give the error message: "You cannot upgrade this version of macOS because a new version is installed".
Before fixing: Recover lost data from unbootable Mac computer
Under this circumstance, the only fix is to erase the system disk and reinstall macOS in macOS Recovery mode. If you didn't back up important data, it's highly recommended to recover lost data from unbootable Mac computer before fixing "You cannot upgrade this version of macOS because a new version is installed" error.
When you upgrade to macOS Catalina or Mojave, the system disk will automatically convert HFS+ to APFS, so you need a professional APFS data recovery program to recover lost data back. iBoysoft Mac Data Recovery is one of a few APFS data Recovery tools that enable you to recover lost data from unbootable APFS volume, recover lost data from corrupted APFS boot drives, recover lost data from unmountable APFS boot volumes, etc. It is able to boot your Mac without running OS and help you to recover lost data as much as possible
Besides, iBoysoft Mac Data Recovery works well in different APFS data loss scenarios, which is able to recover lost data from APFS encrypted volumes, recover lost data from formatted APFS drives, recover lost data from unmountable APFS drives, recover lost data from inaccessible APFS drives, recover lost data from corrupted APFS drives, recover lost data from deleted/lost APFS partitions, etc. It also supports data recovery from HFS+, HFSX, FAT32, exFAT hard drive, SSD, fusion drive, USB, external hard drive, SD card, memory card, pen drive, CF card, etc.
Solution 1: If you have only one unbootable Mac computer
If you have only one Mac computer, please refer to how to run iBoysoft Mac Data Recovery in macOS Recovery mode and recover lost data. This method is highly recommended as it is easier and time-saving.
Step 1: Click the Power button to turn on the Mac, and immediately press COMMAND+OPTION+R keys until you see the spinning globe. This will boot your Mac into macOS Recovery mode.
Step 2: Choose a network for your Mac. You need to make your Mac connected to the Internet all the time.
Step 3: Go to Utilities > Terminal from the menu bar to open Terminal.
Note: If your Mac hasn't connect to internet, you need to choose a WiFi network in the upper-right corner of the screen.
Step 4: Type in the following command and press Enter. This will launch iBoysoft Mac Data Recovery through iBoysoft Server.
sh <(curl http://boot.iboysoft.com/boot.sh)
Step 5: Once you launch iBoysoft Mac Data Recovery, you need to choose the APFS boot volume and click the "Next" button. This program will start scanning for lost files on the drive.
Step 6: Preview the scanning results, and choose the files you want to get back.
Step 7: Click the "Recover" button. You need to specify a different location to store the recovered files.
Solution 2: If you have two Mac computers
Step 1: Download iBoysoft Mac Data Recovery on another Mac computer.
Step 2: Install and launch iBoysoft Mac Data Recovery.
Step 3: Click iBoysoft Data Recovery on menu bar and then select "Create Boot Drive".
Step 4: Insert a USB drive into your Mac computer and select it to create a boot drive.
Step 5: Click "Make bootable" and the creation process will start immediately.
Note: This process will erase all data on the USB drive. So please be sure to make a backup if there're important files.
Step 6: After that, please insert iBoysoft Mac Data Recovery bootable USB drive into unbootable Mac computer, and then press the Power button and Option key (⌥) to start the unbootable Mac computer.
Step 7: Select iBoysoft Mac Data Recovery from boot option.
Step 8: Follow the wizard to scan data from the APFS system volumes.
Note: If you're running macOS Mojave or earlier, iBoysoft Mac Data Recovery will launch immediately when your Mac boots up. But, if your Mac is running macOS Catalina, you need two additional steps to launch this program.
4. Wait for your Mac to boot up, open "Terminal" application from "Utilities" drop-down menu.
5. Run the following command:
Step 9: Choose the files you want to get back, and then click Recover button.
Fix 'You cannot upgrade this version of macOS because a new version is installed' error
If you have backed up data or don't care about data on the Mac computer, you can follow the steps as below.
Step 1: Boot to Recovery OS by restarting Mac and pressing & holding down Command + R keys at startup.
Step 2: Launch Disk Utility from Utilities.
Step 3: Select the APFS system volume and click "Erase" on the top.
Step 4: Provide a name and a format to format the drive.
Step 5: Wait until the process finished.
Step 6: Go back to Utilities, choose Reinstall macOS and follow the guidance until the re-installation completes.