Unable to install Symantec Management Platform with host names that contains an underscore. Symantec Installation Manager (SIM) displays an error entry in the Installation Readiness Check (IRC) during the installation process.
Starting with ITMS 7.5 SP1 release, there is a new IRC that detects whether the hostname of Windows Server 2012 R2 computer contains underscore characters. If yes, then the IRC restricts the installation of SMP on the computer.
Change the hostname on the server to a name without underscores on it.
ITMS 7.5 SP1
SIM 7.5.240 or later