Blue screen on booting Windows 10, error 0xc000000f

[Colonel Cowstore]

Blue screen says "a required device isn't connected or can't be accessed"
I have my rescue USB and I can boot to the OS with it (and from then on everything works fine) but I'd like to restore things to where they were when I could boot without the rescue USB. I've been using Veracrypt for 4 months so far with no problem (booting daily) but I think Windows update 1809 caused this - it's the last update installed and after that I couldn't boot normally any longer.

I've tried all of the options on the rescue USB except 'Restore OS header keys' which from what I can tell is only for when the password is being rejected.
Restore Veracrypt loader to boot menu asks me which disk I want (I can only select the default one that has [Boot] in front) and then there's no feedback, and after that no other option in the rescue USB menu has any feedback until I reset my PC. It's exactly the same with 'Restore Veracrypt loader configuration to system disk' and 'Restore Veracrypt loader binaries to system disk'.

My VeraCrypt version (and the version of the VeraCrypt rescue disk) is 1.23

I'm fully backed up but I'd rather not spend the rest of the day fixing this, decrypting/encrypting or reinstalling Windows and everything else along with it.

Edit: when I tap enter on the blue screen, it says:
The application or operating system couldn't be loaded because a required file is missing or contains errors.
File: \WINDOWS\system32\winload.efi
Error code: 0xc000000e

[Colonel Cowstore]

Ok, solved it.
What I did is go into my MSI motherboard's BIOS and in the boot section went into the 'UEFI Hard Disk Drive BBS Priorities' (this is distinct from the boot order priorities that determine whether you first boot from the USB or HDD or CD or whatever) where boot option #1 was Windows Boot Manager and boot option #2 was VeraCrypt(DCS). I don't know what BBS or DCS are but I reversed the order so that VeraCrypt came first and it fixed everything.
Now I am 100% certain that previous to this fix I didn't change anything in the BIOS for months, so either the Windows 1809 update changed it or it changed something in Windows that made this BIOS setting important.

[Mounir IDRASSI]

Thank you for sharing your experience and the fix.

This is another instance of Windows Update breaking things, which is
starting to appear more and more often lately.
In this context, I have developed several things to fight against these
recurring problems:

- The tool VcFixBoot available at
https://sourceforge.net/projects/veracrypt/files/Contributions/ can be
run after booting Windows manually through Rescue Disk or BIOS VeraCrypt
entry. It will fix the EFI partition content so that Windows will boot
normally without needing the Rescue Disk or changing the BIOS boot order.

- I have implemented a new mechanism in 1.24-Beta
(https://sourceforge.net/projects/veracrypt/files/VeraCrypt%20Nightly%20Builds/)
that ensures that VeraCrypt bootloader remains correctly registered all
the time even after a Windows Update. This should eliminate such kind of
boot issues.

- Also in 1.24-Beta I have enhanced the logic of the repair mode of the
Rescue Disk so it can handle such cases more intelligently.

More beta testers are needed for 1.24-Beta to ensure the quality of the
current implementation but so far it looks good.