You will get surprised to know that Microsoft had a prohibited list for its employee which are of some apps and online service, which stats NOT TO USE. Geekwire, have reported that they had obtained a leaked documents which have a list of prohibited software and services, and those whose use is discourage.
According to Geekwire, Microsoft have put Slack along with Grammarly, and Kaspersky under "Prohibited" category of of the internal Microsoft list. For Slack, company noted that the chat tool do not provide required controls to properly protect Microsoft Intellectual Property (IP).
Existing users of these solutions should migrate chat history and files related to Microsoft business to Microsoft Teams, which offers the same features and integrated Office 365 apps, calling and meeting functionality. Learn more about the additional features that Teams can provide your workgroup. Slack Enterprise Grid version complies with Microsoft security requirements; however, we encourage use of Microsoft Teams rather than a competitive software.Other than this Prohibited category, there is "Discouraged" category also. This category includes Amazon Web Services, Google Docs, PagerDuty and even the cloud version of GitHub. Yeah..! GitHub, the popular software development hub and community is also there which is owned by Microsoft itself. Regarding the GitHub, it is discouraged from using, specifically for "Highly Confidential types of information, specs or code".
For Grammarly,
“The Grammarly Office add-in and browser extensions should not be used on the Microsoft network because they are able to access Information Rights Management (IRM) protected content within emails and documents,” Microsoft said, cautioning that this could lead to the exposure of sensitive data, and noting that Microsoft security is evaluating what can be done to make the technology secure for use within the company.With all these, it is clear that Microsoft's primary concerns is security. Whats your thought in this story, share in comment box.