Argthtjtr

I have many computers encrypted with Truecrypt 7.1a (current version) with the whole drive encrypted. Today one of them shows the Windows 7 splash screen for a moment and then goes into startup repair which can't read the encrypted drive. I've tried the various safe modes and what not.

The solution is to decrypt the drive and then run startup repair to fix the drive. The problem is that is going to take 50 hours. I've started that process for this situation but I need to have a way to cover myself when this happens to the next PC.

What can I do to avoid decrypting the whole drive? I can't be the only one facing this problem so I feel like I must be missing something.

Thanks!

If you're quick enough, you can hit the [F8] button immediately after pressing Enter (after entering your TrueCrypt password) and it will give you the ability to repair your computer or enter any of the safe modes, etc.

Just verified it using Windows 7 Professional and TrueCrypt 7.1.

http://www.truecrypt.org/docs/rescue-disk

If Windows is damaged and cannot start, [...]

Note: Alternatively, if Windows is damaged (cannot start) and you need to repair it (or access files on it), you can avoid decrypting the system partition/drive by following these steps: Boot another operating system, run TrueCrypt, click Select Device, select the affected system partition, select System > Mount Without Pre-Boot Authentication, enter your pre-boot-authentication password and click OK. The partition will be mounted as a regular TrueCrypt volume (data will be on-the-fly decrypted/encrypted in RAM on access, as usual).

You can partition the 500gb disk to 50gb system partition or something like that, then you just have to decrypt 50gb(only the system disk/partition).

You should have access to the Truecrypt portal that will give you a master key for that HD.

Take take the HD out of current workstation and use it on different workstation.

Unlock it with the key and repair.

*Intel i-series can make a critical issues with encrypting software.

The problem you are encountering with using from another computer the Select Device
command with "Mount Without Pre-Boot Authentication"
might be a bug in the latest version 7.1 of TrueCrypt.

From TrueCrypt Forums Accessing TrueCrypt-encrypted System Volume while Connected Externally :

Known Issues

Affects: TrueCrypt 7.1 for Windows

Issue: Volumes cannot be mounted by selecting System > Mount Without Pre-Boot Authentication.

Workaround: Until this bug is fixed, you can work around it by following these steps:

• Click Mount.


• Click Mount Options


• Enable "Mount partition using system encryption without pre-boot authentication"

The best way is to decrypt the Drive/Partition with True Crypt Recovery CD (Created during encryption), then repair the Windows.
This is work great.

The [F8] trick did not work for me and neither did Startup Repair but this was a one line fix to be able to boot again:

bcdboot c:Windows /l en-us /s c:

I feel strongly that this would work before decrypting, but since I had already decrypted before finding this command, I don't know for sure. It took 2 days for researching via a phone, backing up the drive, then permanently decrypting via Truecrypt boot loader, but it did work.

To execute, get to the Windows recovery environment using Startup Repair or a Win 7 cd, mount truecrypt using UBCD4Win (or perhaps from a flash drive may be easier) and run that command above on the letter drive you've selected to mount on.

Props to OP: https://superuser.com/a/937292/551538

If anyone has a way to re-encrypt a system (decoy) partition (1) in a hidden OS configuration I'd love your opinion. Right now it seems like it will prevent my ability to boot to one of the OS's.