Small update for anyone having the same trouble as me. I could not get no peace until fixing this. I basically used the instructions mentioned in the first 2 posts:
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[x86-64] Can't Boot After Completing Installation
Hi. I decided to transfer my Lenovo H505s desktop PC to HTPC. So I've created LibreELEC bootable USB and booted to loader. In the menu (where boot options can be chosen) I pressed 1 and Enter. "No such file or directory" (What? Why?) Anyway few seconds later installer started. After Installation was complete I removed USB and rebooted. But it`s not possible to boot because of Error 1962: No operating system found. Press any key to repeat boot sequence."
I can`t find any solution for this…
I can`t find any solution for this…

calculon
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