Hi, I am also experiencing the same issue, intermittantly I may add (i.e. on browser refresh the login eventually lets me in). I have tried everything upon installing Personas 1 month ago. I have been through the config over and over, checked auths / roles / browser trace etc.
Browser console suggests "sap-system-login-basic_auth=X failed. Please check your system configuration." I have tried configuring / reconfiguring restgui, been over the roles and checked the service Url / Uri etc etc, as discussed in several discussions.
ECC 6.0, Kernal 721, Sup.Pkg.lvl 100
Has anyone got to the bottom of this by any chance? Any help would be very appreciated.;-)