Reduce Risk When Someone Else Can Use Your Personal Device

Start with the device, not the inbox

Set a screen lock on each personal phone, tablet, and computer you use for email. Choose a method supported by the device, such as a passcode or password, and avoid sharing it casually. If your device offers an automatic lock after inactivity, choose a delay that suits how you use it, then lock the screen yourself whenever you walk away. Automatic locking is a backup for distraction, not a reason to leave a device unattended.

A device lock helps limit access to the whole device, including an email session that may still be open. It does not change your mailbox password, end a mail session, or protect a device that is already unlocked. Keep the lock credentials private and follow the device maker’s instructions for setting or changing them.

You finish reading mail on a tablet in the kitchen. Before leaving, lock the tablet rather than relying on the inbox being out of view.

An open mailbox is a separate exposure

If you step away while the mail page or app is open, another person may be able to read or act on messages using the session already on screen. A strong password does not prompt for itself every time you open a message. Avoid leaving mail visible in a shared room, at a reception desk, or on a screen that someone else is about to use.

When you need to leave briefly, lock the device. When you are finished using mail, close the mail view or sign out if that is appropriate for the situation. Closing a browser tab is not necessarily the same as signing out; if you need the account session to end, use the service’s sign-out option and confirm the signed-out state.

Choose the right response for shared devices

On a device used by other people, do not assume that closing the lid, switching users, or closing a tab has signed you out of mail. If you used a browser, sign out of the mailbox before handing the device over, then close the page. If the device offers separate user accounts, use your own account where possible and lock it when you finish. Avoid saving your mailbox password on a device you do not control.

If you use BITTU Mail, sign-in and account actions go through mail.bittuicloud.com. Sign out using the available service control rather than assuming that leaving the page ended the session. The exact controls available can depend on the account and service state; do not assume a particular setting or device-management feature is present.

Keep mailbox credentials private too

Device security and mailbox security protect different boundaries. A device lock limits who can use the device; a unique, hard-to-guess mailbox password helps protect the account when someone tries to sign in elsewhere or when a device is not involved. Do not tell another person your mailbox password merely because they borrow your phone, and do not reuse it for unrelated services.

If optional two-factor authentication is available for your account, it can add a further sign-in check. Availability and setup may vary, so check the account’s current options rather than assuming it is enabled. Never share a one-time code with someone who asks for it, and do not enter a code into a page unless you intended to sign in.

Build a quick handoff routine

Make the final moments before handing over a device predictable. First, check whether mail or another private account is open. Then sign out of mail if the next user should not access that session, close the page, and lock your own device or switch to the other person’s separate user account. On a shared or public device, signing out is especially important; do not rely on the next person to close your session for you.

• Before stepping away: lock the device.
• Before someone else uses it: close or sign out of your mailbox as appropriate.
• Before leaving a shared device: confirm the mailbox is no longer open to that user.
• After a handoff: keep your device and mailbox passwords private.

Confirm the routine without exposing your account

Check the device lock by leaving the mail screen, locking the device, and confirming that access requires the device’s normal unlock method. Do not test this by asking someone to guess your credentials. To check a sign-out, look for the service’s signed-out state; if you revisit the mail site, confirm that it asks you to sign in rather than showing your mailbox. Do this only on your own device, and avoid leaving a real account open as a demonstration.

If you discover that someone has had access to an unlocked device, secure the device first. If you also suspect that your mailbox password is known or exposed, change it through the service’s official account route and review account options available to you. A device lock cannot resolve a password exposure, just as changing a mailbox password does not lock a device that remains open.