Login failed. SPARQL Gateway could not read the response content from the WhoAmI service of the Jazz Team Server, so it does not know if the user is authorized.
Explanation
SPARQL Gateway could not read the response content from the WhoAmI service of the Jazz Team Server, so it does not know if the user is authorized.
User response
Check if the Jazz Team Server running fine and also check the SPARQL Gateway log file for details.