![office 365 display settings office 365 display settings](https://www.mailsdaddy.com/blogs/wp-content/uploads/2020/01/2.png)
![office 365 display settings office 365 display settings](https://mscorp.com.ph/wp-content/uploads/2016/10/lenovo-thinkpad-x1-yoga-front-7.jpg)
If you cannot connect, you need to ensure your firewall is not blocking this, or your ISP is not blocking. If you are able to connect, then you have nothing blocking port 25.
![office 365 display settings office 365 display settings](https://www.msoutlook.info/pictures/region-customize-format-date.png)
From a telnet capable system that uses the same external gateway IP that your PBX will be using use telnet (yes, telnet!) to confim you can connect to Office 365 Exchange Server through port 25. Confirm you can connect using your external IP to Office 365 through port 25. Use your external IP as the IP Address that is authorized to communicate with the Office 365 Exchange server.ĭ.