As before, the base configuration to support the certificate authentication should have been established during the installation; so, this is just a quick test to ensure that all is OK.
Locate the Settings.ini file in the ProgramData\QlikTech\Server folder.
Check the EnableSSL setting is set to 1 (EnableSSL = 1). If this is not set to 1, it means that either something has gone wrong in the installation, or you have missed a step above. You should perform a quick uninstall and retry the installation with the correct options.