1. Protect your password

Your first step should be to make sure your password is well chosen and not shared.

If you need to set a new one, visit the "Security & privacy" section of the Account settings page.

You'll then have to verify your account with a security code, which you can do by email or text.

At the top you'll see when your password was last changed, with an option to change it below.

Just below that, in the section labelled "Security info helps to keep your account secure", you'll find any backup email addresses or phone numbers you've given to Microsoft to help verify your identity if you get locked out of your account.

Make sure these are a good way of getting in touch with you, and are not easily accessible by people you don't trust.

These contact points will also be used to send alerts if Microsoft spots any suspicious activity - you can choose whether or not to receive alerts by phone and whether to have them sent to multiple email addresses, but the primary alternate email must always get alerts.

2. Set up two-step verification

On the same screen you can also set up two-step verification.

Scroll down to the next section of the "Security & privacy" page.

When you follow the link to set it up, Microsoft recommends using a smartphone app, which will vary depending on what kind of device you use.

Windows Phone users can get Microsoft's own authenticator app, Android users can use the Microsoft Account app, and those with iOS devices will need Google's multi-purpose Authenticator.

Each has its own process for setting up, but most will simply require you to scan a QR code displayed on-screen. Once set up, you should be able to use the code generated by the app any time you want to log in to your account.

If you choose not to use an app, or don't have a smartphone, you can have codes sent by SMS to the number you provide, or by email to one of your alternative accounts, but Microsoft will continue encouraging you to opt for the app approach, at least until you tell it to stop.

When you log in with a 2SV code, there will be an option to trust the device you're using and not ask for any more codes, so in future you'll only need your normal password.

Only check the box if you're on a machine you use regularly and know to be kept well-secured.

As part of setting up 2SV, you'll be given an emergency backup code. This is used if you ever lose access to the apps, phone numbers and email addresses provided for 2SV codes.

Outlook.com recommends you print it and keep it somewhere very safe, but if you find it easier to keep it in a file on your (well secured) computer, make sure it's very well encrypted.

In the "Recovery codes" section you can choose to renew the emergency backup code if you no longer have it.

3. Check your settings

You should consider checking the "Security & privacy" page occasionally, to make sure the backup and 2SV contact details are up to date - check that any old devices you no longer have are removed from the "Security info" or "App passwords" sections.

There's no way to monitor which devices have been marked as trusted for 2SV purposes, but at the bottom of the "Security & password" page you can at least remove trust from all machines, cutting off anyone who may have obtained unauthorised access.

There's a whole section of the "Security & Privacy" area dedicated to "Recent activity".

This is the place to go if you suspect someone's been intruding on your account. You can view a detailed list of logins, attempts, 2SV challenges and significant settings changes, and for each one there is further information on the device type and browser or app used, the IP address and location.