While installing a single SOI ActiveMQ server the installer asks for SOI admin credentials (samuser), but after installation, there are no references to these user credentials in any of the config files on the ActiveMQ server.
In pre SOI 4.3 installations, the password was stored in <SOI_HOME>\apache-activemq\conf\activemq.xml.
SOI 4.3
The SOI admin credentials that the installer requests are no longer used in the product. Instead, the manager handles validation of incoming connections at the server itself. We shall update the installer to not ask for the SOI Admin Credentials in a future release, but for now, it may be safely ignored.