According to diskpart, a disk has four partitions:

Partition 1 - Recovery - 11GB
Partition 2 - System - 100MB
Partition 3 - Reserved - 128MB (MSR / OEM Partition)
Partition 4 - Primary - 464 GB

The four volumes are listed as:

Volume 0 - C - Blade - NTFS - Partition - 464 GB - Healthy -
Volume 1 -   - Recovery - NTFS - Partition - 11 GB - Healthy - Hidden
Volume 2 -   - SYSTEM - FAT32 - Partition - 100MB - Healthy - Hidden
Volume 4 - C - Blade - NTFS - Partition - 464 GB - Healthy - Hidden

More details:

• "detail partition" with Partition 3 selected claims that no volume is associated with the partition
• "detail partition" with Partition 4 selected claims that only volume 4 is associated with the partition
  
• "detail volume" with Volume 0 selected displays a list of attributes, plus volume capacity and free space
• "detail volume" with Volume 4 selected displays a single attribute - offline: no
• Removing or setting the drive letter of either Volume 0 or Volume 4 results in the change being mirrored to the other volume.
• The above information was obtained after booting into a Windows PE shell.  Diskpart does not show Volume 4 when running Windows 8.1 from the primary partition.
• Disk Management in W8.1 does show the duplicate volume entry as a Healthy OEM Partition (465 GB). However, it does not indicate the existence of Partition 3 in the disk view.
  

Problems resulting from misconfiguration:

• Disk Manager does not permit management actions on volumes (context menu shows only "help" entry, window menu entries are all disabled)
  
• BitLocker is unable to encrypt the volume, complaining that it is hidden.

Otherwise, the system runs just fine so far.  This is a new 2014 Razer Blade. (Have verified that another new 2014 Razer Blade has the exact same problem, so it's something that Razer misconfigured.  Their support isn't terribly helpful, unfortunately.)

• Edited by tvald Saturday, February 07, 2015 12:38 AM formatting

Hi,

Based on my known, either hidden or mirrored, it doesn't show as what you said. It's most likely OEM manufacturer's specific configuration. I recommend you contact OEM support to verify this.

If it's the special configuration for OEM and working fine, leave it alone.

Meanwhile, give us a screenshot about your disk management and screenshot of running list volume command in normal boot.

No worries, I'm about ready to just wipe the machine and format it correctly.  The OEM (Razer) has stated simply that "BitLocker isn't supported", and they won't investigate it any further.

I'm seeing the same issue.  I just tried installing the hotfixes.  It said 2 of them don't apply to my system.  The 3rd (3000123) installed.  After installing that one, I rebooted.  It did not fix the issue.  I still can't enable Bitlocker.  Any other ideas?

FYI - I gave up, reinstalled, and was then able to encrypt with BitLocker.

As far as I can tell, actually fixing the partition table would require more direct access than diskpart provides, something akin to a hex or binary editor for the partition table, if such a thing were to exist. *shrug* I fortunately discovered this early on and could (disgruntledly) afford the time for a reinstall.

• Marked as answer by tvald Tuesday, March 03, 2015 12:12 AM
• Unmarked as answer by tvald 11 hours 41 minutes ago

FYI - I gave up, reinstalled, and was then able to encrypt with BitLocker.

As far as I can tell, actually fixing the partition table would require more direct access than diskpart provides, something akin to a hex or binary editor for the partition table, if such a thing were to exist. *shrug* I fortunately discovered this early on and could (disgruntledly) afford the time for a reinstall.

• Marked as answer by tvald Tuesday, March 03, 2015 12:12 AM
• Unmarked as answer by tvald Wednesday, July 15, 2015 7:43 PM

Windows tries to protect any partition that it identifies as an "OEM Partition", resulting in undocumented and incorrect behaviors. For example, diskpart will pretend that there isn't a volume associated with an "OEM Partition", unless you boot into a WinPE shell.  The disk management utility will similarly restrict the tools available for manipulating an "OEM Partition".

In the case described by the original post, Razer was overzealous and marked the primary system partition (labeled as C:\) as an "OEM Partition".  Consequently, BitLocker refused to encrypt that partition.

To stop Windows from treating a partition as an "OEM Partition", you need to remove the GPT "required" flag.  Boot into a Linux live cd or usb stick, and use the "gdisk" command:

gdisk /dev/sda  # BE SURE TO PROVIDE CORRECT DEVICE HERE
p      # list partitions - find the partition you need to alter
x      # enable advanced tools
a      # begin set attributes - will ask to select partition
<num>  # enter the partition number from the listing above
0      # toggle flag 0 ('required' flag)
<ret>  # finish set attributes
w      # save and exit

• Edited by tvald 11 hours 41 minutes ago formatting
• Marked as answer by tvald 11 hours 41 minutes ago

Windows tries to protect any partition that it identifies as an "OEM Partition", resulting in undocumented and incorrect behaviors. For example, diskpart will pretend that there isn't a volume associated with an "OEM Partition", unless you boot into a WinPE shell.  The disk management utility will similarly restrict the tools available for manipulating an "OEM Partition".

In the case described by the original post, Razer was overzealous and marked the primary system partition (labeled as C:\) as an "OEM Partition".  Consequently, BitLocker refused to encrypt that partition.

To stop Windows from treating a partition as an "OEM Partition", you need to remove the GPT "required" flag.  Boot into a Linux live cd or usb stick, and use the "gdisk" command:

gdisk /dev/sda  # BE SURE TO PROVIDE CORRECT DEVICE HERE
p      # list partitions - find the partition you need to alter
x      # enable advanced tools
a      # begin set attributes - will ask to select partition
<num>  # enter the partition number from the listing above
0      # toggle flag 0 ('required' flag)
<ret>  # finish set attributes
w      # save and exit

• Edited by tvald Wednesday, July 15, 2015 7:42 PM formatting
• Marked as answer by tvald Wednesday, July 15, 2015 7:43 PM