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Im struggling with this 2017 imac. This imac has a fusion drive which the mechanical drive was giving problems. I replaced it with another one to see if it would let me mount big sur again and I always have the same problem which is that I can’t load macos. I’m not sure if the fusion ssd drive could have problems… any recommendations… thanks!!
Hey Rick, Now that I’m back from my trip (It got cancelled), I will try and assist you in this. Firstly, have you installed an SSD in the imac (SATA or NVMe). If you haven’t this is a good first step to try.. If you do so and this doesn’t work, Reinstall Big sur/Monterey off a USB/EXT SSD (Must be above 32GB and recommend above 64 for headroom). Hope this helps
Ah! You’ve hit the Fusion Drive marriage problem! The hidden PCIe blade SSD is married to the original HDD which you’ve removed. Did you sign the divorce papers?? Nope! ;-} You’ll need to go into OS recovery to gain access to Disk Utility so you can properly break the linkage of the Blade SSD to its dead HDD mate! Reformat the blade drive and make sure you’ve not added a partition. That should break the link - Your divorced! Now the installer won’t get confused. You could also do this using an external bootable OS installer or OS boot drive. But the newer MacOS’s can make things harder with a standard bootable drive if you’ve encrypted your drive. And you could face loading an older recovery OS which doesn’t understand what APFS is so it won’t delete it. Here’s a resource to get older versions of macOS How to get old versions of macOS and here’s how to make a bootable OS installer drive (32GB USB Thumb drive) How to create a bootable installer for macOS Which I find is faster and easier as you don’t need to deal with recovery not loading the newer macOS the system is using (HFS+ Vs APFS confusion issues).
