We are having Microsoft Office 365 issues?
ANSWER: Microsoft Office 365 can be used with Microsoft Exchange and is a popular option for companies and corporations with decades-old setups that are modernizing their applications but still require some of the Microsoft-unique features and software. Although we don’t currently offer a setup service for Office 365, there are a large number of complex DNS records that your domain needs for it to work properly. These records are provided to you during the signup phase of Office 365, and our team is not able to research these for you. However, when you have finished collecting the list of DNS records you require, we are happy to update your DNS for you in CLoudFlare.
Also, to double check that DNS records are fine, you can use this free tool:
https://testconnectivity.microsoft.com
More info: