I'm wondering if someone faces something similar..
I try on Fedora and Windows and also try with different USBs.
I don't think I understand your question. When you say "I try on Fedora and Windows and also try with different USBs." That doesn't make sense to me. Unless you are trying to Virtualbox or KVM boot the LiveExamOS. You're supposed to boot your BIOS or UEFI into the LiveExamOS, not into a hypervisor. So Fedora or Windows should have no bearing on it. The LiveExamOS is a modified Fedora, which is entirely loaded into your RAM sticks during setup.
Give that a try--on my Asus desktop I plugged in the LiveExamOS USB stick, burned by Fedora Media Writer on FedoraWorkstation, and then turned on my PC. I do F12 or DELETE to enter UEFI during PC bootup, then clicked Boot Override on the UEFI-USB stick.
If I am miss understanding you and you're doing all this, please post a larger screenshot. I noticed you have an i386 in the log there--that's a 32-bit CPU archi-type. I think you have to have a 64-bit...but I could be wrong on that.
I have a desktop pc on Windows and a laptop on Fedora, and I try on both of them.
I did the same steps that you mention and got that error...
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