Opencore bootloader suddenly not working

[Edhawk]

Enter the system Bios and reset bios to Optimised Default. Or use the Clear CMOS function on your motherboard.

Either of these should clear any old boot options and re-enable any current boot options in the bios. This should also change how OC sees any boot options.

You will need to reset the bios to work with macOS and set your macOS drive as the primary boot option.

Use the following settings in your bios:

1. Virtualization : Enabled
2. VT-d : Disabled
3. XHCI Hand-Off : Enabled
4. Legacy USB Support: Auto/Enabled
5. IO SerialPort : Disabled
6. Network Stack : Disabled
7. XMP Profile : Auto / Profile 1/Enabled
8. UEFI Booting set to Enabled and set Priority over Legacy
9. Secure Boot : Disabled
10. Fast Boot : Disabled
11. OS Type: Other OS
12. Wake on LAN : Disabled

Dedicated Graphics + Integrated graphics card:

1. Integrated Graphics : Enabled
2. Graphics: PEG/PCIe Slot 1
3. Initial Display Output : PCIe 1 Slot
4. DVMT Pre-Allocated : 128M or higher

 

[greshbin]

Oh boy, do I feel like an idiot now…

I followed your instructions and reset CMOS by loading optimised defaults in the BIOS, but the Windows option was still there following restart. I couldn’t believe it. So, I checked the ‘boot priority’ menu, in an attempt to force disable the windows option there. It was then that I noticed it… The drive for this Windows boot volume is on an SSD I use for data. The flipping Windows EFI had migrated itself to that drive too! Either that, or I had Windows installed to it in the past and never properly formatted.

I’m so sorry for wasting your time Edhawk, you’ve been so generous too, all of you. I feel embarrised.

So, I guess now all I should do is delete the EFI folder from the SSD, or should it be just the ‘Microsoft’ folder therein? I presume an EFI isn’t required for a non-bootable data storage drive.

 

[Edhawk]

It's OK, and an easy thing to do. At least you found the reason for the additional icon on your boot screen.

You can remove the EFI from the Data drive, or delete the Microsoft folder on its own, both should remove the Windows icon from the OC boot screen.

 

[greshbin]

I opted to remove the EFI completely, restarted, then no boot option appeared at all. Seem that EFI was somehow the bootloader for Windows. Fortunately I was able to reinstate the EFI and make it bootable by following this guide.

Happy days. I’m now back in business. I’ll grab the swappable M2 PCIE card to make sure a conflict like this doesn’t happen again. Lesson well and truly learned.

Once I get the time. I’ll start looking into updating OC and potentially MacOS on a cloned drive.

Thanks again all for your help and support. What a supreme bunch of people you are.