What was the original format? If you haven't done too much damage, try to mount the volume with the backup header (Volumes -> Mount Volume with Options). You should already created a separate header backup file.
Final update. I decided to try using EFI again on the new SSD. I did the same steps as before (create an unencrypted partition and copy the old decrypted OS content over), except this time, instead of copying the old EFI that containing the VC boot loaders, I created a new EFI partition and formatted it blank -- copying VC boot loaders might have trigger the GetEfiBootDeviceNumber error. I rebuild the Windows BCD on the new EFI and boot into Windows. Now, I found something interesting and maybe consider...
After messing around with it for a day, I found a work around for this problem. I decided to convert the new SSD to MBR and not use EFI, and I was able to re-encrypt the new drive. After I got it working, I tested using GPT EFI again on another HDD drive, but the system encryption worked on the HDD. I'm not sure if it's because if the new SSD is nvme or not. I'm tempted to try again with EFI on the new SSD, but after spending so much time on it, I'll save that for the next OS upgrade!
I'm hoping someone can help me with this one. My existing encrypted Windows 10 system partition with UEFI is installed on an old SSD. I decrypted the content of the drive and copy them to a new unencrypted SSD. I fix up the UEFI partition so that the new SSD can boot without issues. When I run VeraCrypt to encrypt the partition again, I run into this error: The requested system device cannot be found. Source veracrypt:elevator::GetEfiBootDeviceNumber:617 Anyone know how to fix this? Is it possible...
I also have this problem. At first I thought it was a problem with Windows 10 relocating to a different directory (since I had no issues with Windows 7), but I can confirm that this problem only occurs when redirecting a profile directory in VeraCrypt volume. If I redirect it to a normal volume, this problem doesn't occur. If you go to the user's \AppData\Local\Packages, you can see the Cortana folder keep getting created and deleted. Is there a fix for this?