How do I decrypt a standalone system that is unable to start Windows?
Should your full disk encrypted machine suffer a Windows error that prevents Windows from starting correctly, you may be required to decrypt the disk in order that Boot CD and other Windows recovery methods are able to access the disk contents to correct the error.
To do this you can use the Full Disk Encryption recovery ISO image to burn a CD to boot and decrypt the system without requiring Windows itself to load.
The recovery image can be downloaded here: http://download.deslock.com/download/utility/recovery.iso
Please note if your system is managed by an Enterprise Server then please see this alternative guide: KB210: How do I decrypt a managed system that is unable to start Windows?
If the CD does not boot at all, please check if your PC uses UEFI in the BIOS. The recovery CD requires the BIOS in Legacy mode and may require you to change the setting. You will need to remember to set it back afterwards.
Some PCs offer a boot menu that allows you to boot from a CD after pressing a key, if this is not available, you may need to change the boot order in the BIOS to put the CD/DVD drive first.
Note: ensure a full sector-by-sector backup of the existing hard drive has been taken before attempting recover.
See this article for details: KB70 - How do I perform a full sector by sector backup of my hard drive?
Decrypting the Workstation
If you do not reach this prompt within a few minutes, it is likely that your PC hardware is not compatible and you should follow this article, http://support.deslock.com/KB281, instead, even if you are not using UEFI.
If the Recovery tool is unable to locate the DESlock+ encryption information, it will offer to search for the required boot files. Please see http://support.deslock.com/KB222 for more details.
If the above did not work, please click here to view the Recovery Overview: KB346 - DESlock+ Full Disk Encryption Recovery Overview
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