I tried to install Windows 10 Pro using BootCamp and now the EFI boot screen is blank (black)

[dtelena]

I am using a Mac Pro 2013 6-Core 3.5GHz 64GB RAM Dual D500 machine with a fresh install of macOS Catalina 10.5.3 which was working like a charm (flawlessly) until I tried to install Windows 10 Pro (64 bits) using BootCamp, everything went fine until macOS asked to reboot the machine to continue the installation of Windows 10 but when booting the machine the EFI boot screen went blank (black) and nothing happened. I waited several minutes and powered the machine down and tried reseting several times and nothing happened and even tried reseting PRAM, SMC, pressing Alt-Option key in order to try to boot from a USB flash drive which I have with a fresh copy of macOS Catalina 10.5.3 or even booting and pressing D to diagnose the machine and nothing happens (always a black screen) !!!

One time I tried to boot from the USB flash drive (pressing Alt-Option key) and it occurred to me to press the right arrow key (right directional key) and then Enter key just to discard any display problems (image not showing) with my Apple Thunderbolt Display and boom !!! the machine booted again to macOS Catalina 10.5.3 and all the data and software was already there just like it was previously to trying the BootCamp installation of Windows 10 Pro... so for sure something happened to the EFI boot info of the machine, I mean is there but not showing at all (not even pressing Alt-Option key or pressing D for Diagnostics) but now the machine boots to macOS again but I have no way to boot from other drives or run diagnostics because the screen is always black.

Has someone happened this? How could I fix it without reinstalling a fresh copy macOS again? Terminal commands? Thanks !

 

[dtelena]

I tried re-installing macOS Catalina 10.5.3 again but without formatting the SSD (not a fresh or clean install) and everything is the same, this means no EFI boot image on the screen regardless if I run the diagnostics (pressing D before turning on the machine) or the pressing At-Option when the start-up chime sounds to choose where would I want the machine to boot from.

It is weird that I can boot to macOS Catalina just fine but can't see any EFI boot screen, it seems like some boot files were damaged or corrupted when I tried to install Windows 10 Pro (64 bits) using BootCamp.

The Windows 10 Pro I tried to install was the latest one so far (November 2019 ISO image) which was downloaded directly from Microsoft.com

Any suggestions or ideas ?

P.D.: Forgot to mention that I also run Disk Utility and checked all volumes for errors (First Aid) and everything is OK, no errors at all !!!

 

[Dana Hense]

I hate to say it was this simple, and I hope it is as simple for you. I had the EXACT same issue as you, on a trashcan Mac Pro. I had to read your thread just to get out of the blank screen situation. I happened to have SIP enabled at the time. So I booted into macOS recovery mode, opened up a terminal and typed csrutil disable. then I booted back into Win10 (1909) and like a miracle, it worked. Hope it works for you!

 

[teachandtech83]

I had a similar problem (black screen without cursor) with imac 2010 21,5" i3. Even installing win7 on hybrid partition, same black screen problem, but discovered that external monitor worked. Well, solutions online state to remove atikmdag.sys from windows/system 32/drivers folder, but this makes the gpu to not work properly. You will not get the black screen again, but wont be able to control screen brightness. The other solution, to boot in secure mode and leave native windows driver for display adapaters, solve the black screen but you wont be able to adjust screen brightness either.

What worked for me was to install a 2009 driver for ati found with 3dpchip program (search for older versions when you open the site from the program when clicking on gpu). No black screen anymore and i can control the brightness too. I think that all the forums on internet discussing this problem aren't aware that this may be only a driver issue.

 

[teachandtech83]

I had a similar problem (black screen without cursor) with imac 2010 21,5" i3. Even installing win7 on hybrid partition, same black screen problem, but discovered that external monitor worked. Well, solutions online state to remove atikmdag.sys from windows/system 32/drivers folder, but this makes the gpu to not work properly. You will not get the black screen again, but wont be able to control screen brightness. The other solution, to boot in secure mode and leave native windows driver for display adapaters, solve the black screen but you wont be able to adjust screen brightness either.

What worked for me was to install a 2009 driver for ati found with 3dpchip program (search for older versions when you open the site from the program when clicking on gpu). No black screen anymore and i can control the brightness too. I think that all the forums on internet discussing this problem aren't aware that this may be only a driver issue.

unfortunately,today i got the same problem.Black screen again. Only tweaking with externalmonitor i was able to unfortunately,today i got the same problem .Black screen again. Only tweaking with external monitor (choosing to which display to output, via right mouse button-screen resolution-display) i was able to maintain the image on the imac lcd. Cant do this every time i have to use imac. Not practical. No solutions for that on the internet, not even in apple official forums. A pitty....