@Don Mangiarelli, Thanks for posting in Q&A. For the warning, after click "Yes", can we sign in with the credential of an Intune administrator role. or Global administrator role which have an assigned Intune license?
Meanwhile, please ensure the Internet Explorer Enhanced Security Configuration is turned off on the server.
Make sure the network requirements are all met.
https://learn.microsoft.com/en-us/mem/intune/fundamentals/intune-endpoints?tabs=north-america
However, if it is still failed, please get screen shot of the new error to clarify.
Please try the above suggestion and if there's any update, feel free to let us know.
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