I found this on https://answers.microsoft.com/en-us/outlook_com/forum/oemail-osend/emails-are-blank-when-opened/60a75792-97a1-4493-85c6-5082c5b17e99
Hello, under Outlook options, go to Advanced, then navigate to Display, and uncheck "Disable Hardware Graphics Acceleration" if it is checked. Restart your app, or log out if possible, then see if the contents of your emails load up.Hope this helps and let me know if you have further questions!
I did this and it helped me so I am passing the information along.