Microsoft Remote Desktop Error Message: HTTPEndpointException: 4, The non-proxy http connection failed to connect with the message: 500 Internal Server Error

Question

Dear Microsoft Remote Desktop Geniuses:

I am getting this message when I try to login to my work computer:

HTTPEndpointException: 4, The non-proxy http connection failed to connect with the message: 500 Internal Server Error

What is the problem and how do I fix it?

Please try and avoid acronyms or jargon in your response.

Thank you.

Zepli