In my previous posting, I indicated that my attempts to install Linux on the T100 had eventually lead to my bricking the machine and, after it had been restored to health by an Asus Service Centre, I was planning to sit back and see how things developed. However, in a comment to my posting, “tr3w” suggested that I should continue using Linux through a bootable USB drive. Then, recently, in the Asus T100 Ubuntu Google+ Group, Ciprian Negrila indicated that the “Magic Stick” software would allow either Ubuntu or Android to be booted from a USB drive – without the dreaded mmcblk0rpmb timeout errors! Now, this sounded too good to miss, so I downloaded the Magic Stick package, installed it on a USB drive, disabled Secure Boot on the T100, and booted into the USB drive – only to be greeted by a “Preparing BitLocker Recovery” screen!
This initially had me confused since most web sources, including some Microsoft pages, insist that BitLocker is only available in the Pro and Enterprise editions of Windows 8.1. But, my T100 is running the basic Windows 8.1. However, Disk Manager clearly showed that both my main Windows partition (drive C:) and my dedicated data partition (drive D:) were both encrypted with BitLocker. The questions then became, how did encryption get turned on and, more importantly, how does one turn it off?
Turning off BitLocker is not an intuitive process. In my case, calling up the Security tab in Control Panel showed an option for Encryption, but the only available process was to “Back up the security key”. In fact, my login credentials as both a regular user, and as a “normal” administrator only provided this single encryption option. By default, the key is stored “in the cloud” – under a Windows account. It turns out that the latter feature is a major clue.
In fact, it may be that I inadvertently established disk encryption with BitLocker by (stupidly) starting to follow Microsoft’s instructions to set up Windows on the T100 after the machine had been restored to factory settings. (I bailed out on this and set up a regular account with my usual userid and password.) The default setup process is to use a Windows account to login and, if you go this route, Redmond, in its unerring wisdom, implements disk encryption using BitLocker.
There seems to be lots of information about how to turn BitLocker on, but a dearth of details on how to turn it off. The trick seems to be to set up an Administrator’s account on the T100 using the logon credentials for a Microsoft E-mail account. This will require providing a valid E-mail address for a Microsoft account, and probably requesting a security code that will be sent to this address.
Logon to Windows on the T100 using this Administrator’s account. Swipe in from the right on the screen and bring up the Search box. Type BitLocker and an option to “Change device encryption settings” should be available. Select this option to go to the settings screen, scroll down to the “Device encryption” section which will indicate that “Device encryption is on”. Press the button marked “Turn off” and sit back while the operating system decrypts your drive(s).
A beginner’s guide to BitLocker, Windows’ built-in encryption tool
Windows 8.1 Will Start Encrypting Hard Drives By Default: Everything You Need to Know