Recently i had my Outlook font changes automatically.And the font looks small and weird. After going through some forums, I found out it is the office patch issue.
Please run the following to update the new office patch.
(Click the pictures to see clearer)
1. Go to File
5. After clicking Update Now, Office Click-To-Run application will start to update the office products. Please quit all office products include Skype for Business
6. Update will be done roughly in 5 to 10mins. After that, open your Outlook again