Been installing and trying different Linux OS on external hard drive. First was Linux mint mate. Had no problems. Then I installed ubuntu 20.04 and now I see UUI and when I tried to reinstall Linux mint I get this: verification failed: (Ox1A) security violation. After that wants me to perform MOK maniment
I'm sorry, but HP only warranties their PCs for usage with the OS that comes preinstalled.
IF you replace that with a Linux distro, or add a Linux distro, then you assume full responsibility for maintaining that -- including solving any problems with booting the other OS and/or installing the other OS.
Your best bet for support now is to contact the support forum of the distro you are using.
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