Solution : https://service.sap.com/sap/support/notes/1318150 (SAP Service marketplace login required)
Key words :
1 sapinst server instances installation fails windows registry permissions reason, create registry key software\sap\<sid>, local operating system administrators group, key hkey_local_machine\software\wow6432node\sap\, local sap system administrators group, 1 server instances fails, hkey_local_machine\software\sap\mdm, hkey_local_machine\software\sap\, sapinst log file, sapinst log directory
Related Notes :
1329424 | SAP NetWeaver MDM 7.1 SP02 Release |
1249503 | Further Notes about Installation of MDM 7.1 |