Win 7 to 10 0x8007001F upgrade error

I have user that I've attempted to upgrade to Windows 10 but it failed with error0x8007001F. To date, I've upgraded at least 200 machines and counting using the same steps and haven't had a problem. All of them are Dell Optiplex models that support Windows 10. Steps I've taken so far are :

CHKDSK C: /F
Remove and re-install audio driver (suggested by Googling)
ESET Antivirus removed
also tried running as local admin account but no luck

I did notice that he has a strange empty E: partition that was created when I used AOMEI Backupper to clone him to SSD a while back. There seems to be nothing on the E:\ but it appears as a primary partition. Can I use partition software to remove it safely? It's the only thing that stands out to that would be different from all the other computers. Any ideas? Any logs I can check for details as to what may have caused the upgrade to fail?









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AOMEI got back to me and it looks like that E: is safe to remove as that PC is still MBR

"Apologies for the inconvenience caused to you.According to the screenshot, it seems that the E drive was an EFI partition from your source PC, it is a very important partition for a bootable UEFI system.
and normally it is a hidden partition on the windows system.
but during the cloning process, this EFI partition lost its job as your target disk is MBR type, the role of EFI is replaced by System reserved partition( in your case, it is the RECOVERY partition) or just the C partition.


AOMEI Backupper fails to recognize it too after the clone ( it is a bug), so it reveals its hidden property, and assign a drive letter for it.
Based on your case, you can just delete it, or unhide it by deleting the drive letter under Disk Management."