Spam filtering and email security

Spam filtering catches the great majority of unwanted mail automatically, but no filter is perfect. A little care from you makes the filter noticeably better and, more importantly, keeps you safe from the messages that do get through.

Training your spam filter

• Mark, don’t delete. Using “mark as spam” rather than simply deleting teaches the filter what you don’t want. Deleting teaches it nothing.
• Rescue misfiled mail the same way. If a legitimate message lands in spam, mark it “not spam” rather than dragging it out.
• Check your spam folder weekly. Invoices, delivery notifications and password resets are the messages most often misfiled.
• Add regular senders to your contacts. Most filters treat known contacts more favourably.
• Be patient. Filters learn over weeks, not hours.

Recognising phishing

Phishing messages try to trick you into revealing passwords or banking details by impersonating an organisation you trust. They’ve become considerably more convincing, but the warning signs remain consistent.

• Manufactured urgency. “Your account will be suspended in 24 hours.” Real organisations rarely give you a deadline measured in hours.
• A generic greeting. “Dear Customer” from a company that knows your name.
• A sender address that doesn’t match. The display name is trivially faked. Expand the actual address and look at the domain carefully — lookalike domains substitute characters that read almost identically.
• Links that go elsewhere. Hover over a link before clicking and read the address that appears. On a phone, press and hold to preview it.
• Requests for credentials. No legitimate organisation asks for your password by email.
• Unexpected attachments. Particularly .zip or .exe files, or documents asking you to “enable macros”.
• Small errors. Odd phrasing, inconsistent formatting or a slightly wrong logo.

If you think you’ve been caught

1. Change the password immediately for the affected account, from a device you trust.
2. Change it anywhere else you used the same password. This is why password reuse is dangerous.
3. Contact your bank straight away if you entered banking details.
4. Enable two-factor authentication wherever it’s offered.
5. Scan the device for malware if you opened an attachment.
6. Tell us if it involved your Flexi Networks account so we can secure it and watch for unusual activity.

Protecting your mailbox

• Use a strong, unique password of at least 12 characters, not reused anywhere.
• Enable two-factor authentication where available.
• Be careful where you publish your address. Addresses posted publicly on websites are harvested automatically.
• Use a secondary address for competitions, downloads and shopping sign-ups.
• Keep your devices updated. Security updates matter.
• Don’t check mail on public Wi-Fi without care — and never on a shared computer.