We originally wrote this story back in May, when news hit that more than 270 million email account details were being sold on Russia’s black market following a huge hack, with 24 million belonging to Gmail, 33 million to Hotmail and 40 million to Yahoo Mail users. With no way of knowing whether your email address had been affected, we advised you to change your password to avoid security implications (it's a good idea to routinely do so in any case).

Since then, in September September 2016 news broke that Yahoo user account details had again been stolen, with at least 500 million user account details at risk following a 2014 data breach. And now, in December 2016, the company says one billion accounts are affected by an entirely separate data breach dating back to 2013. We strongly advise you to change your Yahoo login details, which we explain how to do so below. Plus: How to change your Gmail password; how to change your Hotmail password. Also see: How to create a strong password

How to change your Yahoo Mail password

• Log into your Yahoo Mail account at login.yahoo.com

• Tap on the cog icon at the top right of the screen

• Choose Account info

• Select the Account security tab

• Click on Change password

• Enter a new password, re-enter it to confirm, then click Continue

How to change your Gmail password

• Head to myaccount.google.com

• Under Sign-in & security choose ‘Signing into Google’

• Under Password & sign-in method click on Password

• Log into your Google account

• Enter a new password (at least eight characters), then re-enter it and click Change password

How to change your Hotmail password

• Log into your Hotmail account at outlook.com

• Tap on the cog icon at the top right of the screen

• Choose Options

• Select the first option under Managing your account for Account details

• Select the Security & privacy tab

• Choose Change password under Account security

• Microsoft will verify it is you requesting to change your password: enter your email address and click Send code. When you receive the code, enter it and click Submit

• Now enter your current password, new password (at least eight characters and case-sensitive), then re-enter the password and click Save

Read next: Best antivirus for Windows PCs, laptops and tablets

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