I have checked recent Windows Update changes to see if anything has automatically been applied which could have caused this to occur.

These errors started to become present on the but may changes may have been applied on the weekend of 4th & 5th of Feb. We run Business Central on one of our servers and have also been running into SSL/TLS errors on our API calls, so it definitely seems like some security change has occurred on our network that we are not aware of, and this is enforcing security certificates to be required in order to pass traffic to these different web services. Now our services with Microsoft are staggering as a result of this change in our network, including pages taking minutes to load in Sharepoint, messages taking up to a minute to show in Teams and One Drive can't download cloud stored files as it times out. We also notice several websites are either blocked outright by producing an ' ERR_CONNECTION_REFUSED' error or prompt that notifies the user that revocation information for a security certificate is not available and asks if they would like to proceed. Looks to be something blocking this connection on our network. While connected to our internal network, we cannot reach the Microsoft Update Servers to conduct Windows Updates or call any data from their servers if we were to run the office 365 apps.exe in order to install the latest version. Our work has recently come across a network issue which seems to be getting worse by the day.

Latest version of office 365 business