Restoring computer with Windows 10

[Erik]

Hi,

I have an AES encrypted disk with password that I want to permently decrypt. There was an update of windows 10 and that f#cked up my system. The system won't boot anymore. The disk is encrypted in Truecrypt mode and I can decrypt it when it is attached to another computer and I give the password of the disk.
How can I decrypt this disk on this computer and remove veracrypt from the disk? So this disk is connected to another computer with veracrypt and I want to remove veracrypt permantly, so I can restore windows 10. This HDD must be fully decrypted. I have no rescue disk. I have a secondairy data disk that uses a file from this HDD to decrypt the secundairy disk. I tried to decrypt this secundairy disk, but it fails. Probably because I used 2 files to decrypt it. So please help me restore windows 10 on the encrypted C drive to be able to restore the data disk.
Any help would be appreciated.

Kind regards,
Erik

[Enigma2Illusion]

Hi Erik,

With the OS drive mounted on another computer as a secondary drive, can you mount the OS partition using the option "Mount Without Pre-Boot Authentication" in TrueCrypt mode?

Is your OS drive using UEFI or MBR?

If you can mount the OS drive on the other computer, the VeraCrypt Rescue Disk may be available to copy to the other computer so you create a rescue disk to perform system decryption on the original computer on the original OS drive.

https://www.veracrypt.fr/en/VeraCrypt%20Rescue%20Disk.html

Additionally, if you are able to mount the OS drive on the other computer will allow you to copy critical data to another drive.

[Enigma2Illusion]

I just realized that you stated:

The disk is encrypted in Truecrypt mode and I can decrypt it when it is attached to another computer and I give the password of the disk.

VeraCrypt can only access TrueCrypt. Never could VeraCrypt create a TrueCrypt volume or create a TrueCrypt system encryption.

Hence, unless you can find the TrueCrypt Rescue Disk by mounting the OS drive on the other computer, there is no means for VeraCrypt to decrypt the system encryption in order to remove the system encryption.

The only option would be to mount the OS disk, copy the data you need to another drive and reinstall the OS on the original PC.