There are two ways to have an Ad-Free Outlook when managing your email.
For only $19.95 USD a year, you’ll see no graphical ads in your inbox with Ad-free Outlook.com and if you previously used Hotmail Plus, your account will be automatically upgraded to Ad-free Outlook.com.
To save a little money, switch to Google Chrome and utilize an ad blocking extension (such as Adblock Plus) from the Chrome Web Store.
Your network connection or host file can be tweaked to block the loading of images from ad servers and covers any browser used at the time. Please keep in mind that you need access to the Local Administrator account on the computer to make the changes since it will affect all users of the system.