Aurora R4 - Won't Recognize Boot Device (SSD) after Bios Update from 07 to 09

Have an Aurora R4 -  Service Tag <ADMIN NOTE: Service tag removed per privacy policy>

Was on Dell Support site - trying to update BIOS from version 7 - picked what I thought was next version (by date) - turned out to be version 9.

Followed the steps to download this version and do the update - everything seemed to be working fine. Had a "pop-up" menu with a progress bar - showing update was from Bios 7 to Bios 9 - and then got a message that computer needed to "restart" for changes to take effect. All good to that point - but then:

After reboot - Machine at first would not show anything on monitor at all.

Reached one Dell tech who had me disconnect all cable and hold power button down for 1 minute (can't remember what she called this - some kind of reset).

Machine now boots into initial start-up mode - but will NOT proceed into Windows. (Computer had been updated from Windows 8 original configuration to Windows 10).

Rep had me looking at the Boot options - and it appeared to be stuck in "UEFI" mode - Rep said with only one hard drive - the machine should be in ":Legacy" mode ??  Would NOT toggle between these modes.

I tried re-booting a few times - hit the F12 key and WAS able (I thought) to change boot mode to Legacy.  However machine will still proceed into starting windows.

With setting on Legacy - I am getting message that says something like "insert boot media in boot device" - basically it appears to not recognize the hard drive.  May try resetting to UEFI mode - but had same problem there - essentially it acts like it doesn't have a bootable OS available.

The hard drive on this machine was changed about two year ago - to a 500 gb Samsung Pro SSD.  Really doubt that has died - but I guess anything is possible.  When I go into the Boot options screed (F12) - it does list the Samsung as the boot device - does this mean it is turning it on??

I believe my son did an update directly with Microsoft from Windows 8 to Windows 10. Computer was working perfectly prior to all this - was just trying to get the BIOS updated so he could possibly install an updated graphics card like a 980 Ti.

REALLY FRUSTRATED now - I have to go on a business trip tomorrow afternoon - and now I won't be just the dad who is always traveling - I am the dad who crashed my son's computer before I left.

Jim

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