Students receiving "Something went Wrong" Message

Tom K Thank you for the link to the URLs. My IT department is saying the following message,

"Patrick and I saw the list when we were working with operations. The problem is that if our firewall were blocking the URLs, none of your students would be able to login. Since you said that it works 50% of the time, the URLs are getting through. The only exception would be if Microsoft is directing any of that traffic to servers in other countries that are being blocked. We would need a list of those countries to determine if that could be an issue. We would also need a list of ports they are using."

Is there anyway to resolve this?