How can I improve Gmail security?

Log in to your Gmail account as usual and click the Settings link at the top-right of the main page. Next, click the Accounts and Import link, then click the link for Other Google Account settings. When the Google accounts page opens, click the Using 2-step verification link under Personal Settings. Verification works with both landlines and mobile phones, so ensure that the phone intended for use with the service is to hand and click the button labelled ‘Set up 2-step verification’.

Android, BlackBerry and iPhone users can use a special free app with 2-step verification – this is covered in Step 6. Owners of other types of mobile phone, or anyone who wants to use the service with a home phone, should select Other from the dropdown menu. Choose the phone’s home country and then type in the telephone number, without the leading zero or the international dialling code. If your phone number was ‘07999 123 456’, for example, you would type ‘7999 123 456’. Now choose whether you want verification codes to be sent by SMS text message (mobile phones only) or by automated voice message (mobile phones and landlines).

When you have selected the appropriate code-delivery option, click the ‘Send code’ button to test the service. Within a few seconds the code will be delivered by text message or automated voice call, according to the selected option. Make a note of the code, if necessary (codes expire after a short time, so it is OK to write them down), then type it into the Code box on the web page and click the Verify button. Click the Next button to continue.

Assuming all is well a confirmation page appears, so just click the Next button to continue. Next, a page with a series of ‘backup’ verification codes will appear. This page should be saved or printed, and kept in a safe place – the backup codes can be used for verification purposes if the registered telephone number is unavailable for any reason. Click to tick the box to confirm that the codes have been saved, then click the Next button.

Google also insists upon having a second telephone number as a backup for verification code delivery – this is essentially a repeat of Step 2. With this step complete, a summary page will open with a large blue button labelled ‘Turn on 2-step verification’. Check that the details for verification code delivery are correct, then click the button to continue and you’ll be logged out of your Gmail account. The next time you log in, type in your username and password and a verification code will be sent by the method chosen in Step 2 – this must be entered on the web page that appears to complete the login process.

Using Gmail verification with an Android, Blackberry or iPhone smartphone requires downloading and installing the appropriate free app: on-screen instructions for this are given when one of these options is selected in Step 2. Once the app is installed and linked with a Gmail account, it generates a new verification code every 30 seconds: this is used for the Gmail login process, rather than a code sent by Google. Since an active mobile phone isn’t required for this to work, this is an ideal option for places where mobile phone network coverage is patchy.