I have the same issue, here is the tail of my launcher's log :
[Error: 2020-06-05 15:22:21.8588262: MinecraftServicesApi.cpp(90)] Error while sending request to [https://api.minecraftservices.com/authentication/login_with_xbox]{{ [Error: 2020-06-05 15:22:21.8588508: MinecraftServicesApi.cpp(93)] https://api.minecraftservices.com/authentication/login_with_xbox responded with: Response code: 401 Response body:}}{{{ "path" : "/authentication/login_with_xbox", "errorType" : "UnauthorizedOperationException", "error" : "UnauthorizedOperationException", "errorMessage" : "Unauthorized", "developerMessage" : "Unauthorized", "details" : { }}}{{}}}
[Error: 2020-06-05 15:22:21.8588262: MinecraftServicesApi.cpp(90)] Error while sending request to [https://api.minecraftservices.com/authentication/login_with_xbox]
Cédric PIERRE
I have the same issue, here is the tail of my launcher's log :
[Error: 2020-06-05 15:22:21.8588262: MinecraftServicesApi.cpp(90)] Error while sending request to [https://api.minecraftservices.com/authentication/login_with_xbox]{{ [Error: 2020-06-05 15:22:21.8588508: MinecraftServicesApi.cpp(93)] https://api.minecraftservices.com/authentication/login_with_xbox responded with: Response code: 401 Response body:}}{{{ "path" : "/authentication/login_with_xbox", "errorType" : "UnauthorizedOperationException", "error" : "UnauthorizedOperationException", "errorMessage" : "Unauthorized", "developerMessage" : "Unauthorized", "details" :
{ }}}{{}}}