If your device is lost or stolen, nobody can read what is on it.
What it is
Everything stored on the device is scrambled. Without your password the contents
are unreadable, even to someone who takes the drive out and plugs it into
another computer.
That last part is the point. Your login password protects the machine while it
is running and protects nothing at all against someone who unscrews the drive.
Encryption makes the data itself useless to them.
Why it matters
This is the most valuable control on the list. It is the difference between a
lost laptop being an annoying expense and a company wide incident involving
customer data.
On Windows: BitLocker
Windows calls this BitLocker. Turn it on under
Settings, Privacy and security, Device encryption. Leave the laptop plugged in
and awake until it finishes: it is not protecting you until it has finished,
not merely started.
No such setting? You are on Windows Home
This is the most common reason this card is red on
Windows, and it is not something you did wrong. Microsoft does not put BitLocker
in every edition of Windows:
- Windows Pro or Enterprise. Full BitLocker. You can switch it on
yourself · this is the edition every work machine needs.
- Windows Home. No full BitLocker, so it cannot be made compliant.
Home does not mean a personal device · a company-bought laptop can be on Home simply
because it has not been upgraded yet.
Every work machine must be Pro or Enterprise
· company-owned or your own. Everyone is entitled to a licence, so this is an upgrade,
not a purchase.
The fix is a licence, not a setting.
Ask the Access Hotline for a Windows Pro key. It is an in-place upgrade:
Settings, System, Activation, Change product key. Nothing is wiped, nothing is
reinstalled, the machine restarts, and BitLocker appears.
To check your edition: Settings,
System, About, and read the line marked Edition.
On a Mac: FileVault
macOS calls this FileVault, and unlike Windows there
is no edition problem: every Mac has it, on every model, and it is simply off
until someone turns it on. Recent Macs encrypt the drive at rest anyway, but
only FileVault ties that to your password, which is what makes a stolen Mac
unreadable rather than merely locked.
System Settings, then Privacy and Security, then
FileVault, and turn it on. You will be offered a recovery key. Keep it
somewhere that is not this machine: a recovery key stored on the drive it
unlocks is not a recovery key.
On a phone or tablet
Nothing to switch on. iPhones, iPads and modern
Android devices encrypt themselves as soon as a passcode is set, and unlock with
it. If this card is red, the reason is almost always that no passcode, PIN or
biometric is set at all.
On Linux: LUKS
Linux uses LUKS for full-disk encryption, and unlike
Windows and macOS it is normally chosen when the system is installed, not switched
on afterwards. Enabling it on an existing install usually means backing up and
reinstalling, so if this card is red, talk to the Access Hotline first: on a
work machine we would rather reprovision it encrypted than have you attempt an
in-place conversion. To check your current state:
lsblk (a crypt layer means LUKS is active), or
sudo cryptsetup status on the root device.
If the option is missing or greyed out on a work laptop, only
IT can change that. Ask rather than forcing it.