I am in a really dire situation now, since I currently have a totally inaccessible Mac Pro.
This is what happened:
I installed the Big Sur Beta on an external SSD drive (after allowing external boot first). At first things went well, it took a while but then I heard that famous boot sound again and was into Big Sur. I played a while with it (did not like it too much) and then rebooted into Catalina. I wondered why that startup sound still was there, and it dawned on me that there might have been a firmware upgrade as well. But did not think too much about it first, went on to Catalina and disconnected the drive.
But then the problems started when I switched to my bootcamp install later on. At first I saw the windows logo, but then black screen ... then an automatic restart and then I landed in windows recovery. Uuuups! Then I choose to restart and then I got at least the windows login screen. But no reaction to anything, no mouse no keyboard. After while restart, into windows recovery again. (This at least seems to allow some interaction.)
And the thing is, directly after powering the machine on, I get this little spinner you can see if you switch from macOS to bootcamp via the control panel (which I initally did). In other words, no Apple logo. That also means, absolutely no reaction to the usual startup keys like alt, CMD+PR etc. So I also cannot change my startup OS to macOS back again, also no macOS recovery, just nothing but a constantly restarting windows. Since windows also does not allow me to login, I now effectively sit before a bricked machine. The only thing I could do is a reset/reinstall of windows, but not sure if this will lead me to anything, or make things even worse.
It just smells like there is a problem with the updated firmware (if it actually was updated, but the startup chime is still there, even in this state).
Any ideas? Any help is really really appreciated.
This is what happened:
I installed the Big Sur Beta on an external SSD drive (after allowing external boot first). At first things went well, it took a while but then I heard that famous boot sound again and was into Big Sur. I played a while with it (did not like it too much) and then rebooted into Catalina. I wondered why that startup sound still was there, and it dawned on me that there might have been a firmware upgrade as well. But did not think too much about it first, went on to Catalina and disconnected the drive.
But then the problems started when I switched to my bootcamp install later on. At first I saw the windows logo, but then black screen ... then an automatic restart and then I landed in windows recovery. Uuuups! Then I choose to restart and then I got at least the windows login screen. But no reaction to anything, no mouse no keyboard. After while restart, into windows recovery again. (This at least seems to allow some interaction.)
And the thing is, directly after powering the machine on, I get this little spinner you can see if you switch from macOS to bootcamp via the control panel (which I initally did). In other words, no Apple logo. That also means, absolutely no reaction to the usual startup keys like alt, CMD+PR etc. So I also cannot change my startup OS to macOS back again, also no macOS recovery, just nothing but a constantly restarting windows. Since windows also does not allow me to login, I now effectively sit before a bricked machine. The only thing I could do is a reset/reinstall of windows, but not sure if this will lead me to anything, or make things even worse.
It just smells like there is a problem with the updated firmware (if it actually was updated, but the startup chime is still there, even in this state).
Any ideas? Any help is really really appreciated.