Windows 11 Win11 not booting after Win10 to 11 upgrade on Dell Precision 5820. Win11 boots when manually selecting UEFI boot option only.

[BartD07]

Hello, I have a Dell Precision 5820 PC with an SK Hynix P31 1TB NVMe SSD in a Sybrent PCIe to NVMe M.2 adapter in the first PCIe slot. On it I installed Windows 10 in UEFI mode last year and it has been running great. Recently I decided to upgrade to Windows 11 through the Windows Update process. The upgrade tool showed all checks so I did not foresee any issues. The upgrade process continued without issues and at the last restart it booted to the dell diagnostics screen which showed "No bootable devices found". From there I restarted went to the BIOS changed to legacy with legacy roms and tur

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