KB35894: "Failed to start service Unexpected error occurred. Operation not permitted" error message appears when stopping MicroStrategy Intelligence Server on Linux

SYMPTOM:
When stopping the Strategy Intelligence Server 9.0.2  on a CentOS Linux environment, the following error occurs:
 

Failed to start service. Unexpected error occurred. Operation not permitted.

Additionally, the 'Service Startup' options are grayed out in Service Manager:

CAUSE:
The Intelligence Server is not registered as a service in configuration.
ACTION:
To register Strategy Intelligence Server as a service in UNIX or Linux, login as the ROOT user (or should be part of the systems group) using the following two options:

1. Strategy Configuration Wizard (Check the 'Register Intelligence Server as a Service' box after input the Port Number.)
2. Using MSTRCTL utility (~/MicroStrategy/bin directory, by command 'mstrctl -s IntelligenceServer rs' )

For detailed steps on above two options to register Intelligence Server as service, refer to below KB article: 
KB13000  How to register MicroStrategy Intelligence Server Universal 8.1.x and later as a service?
WORKAROUND:
mstrctl utility tool with below command can be used to stop the Intelligence Server as a workaround:  
./mstrctl -s IntelligenceServer stop 
For more details of the MSTRCtl utility, refer to below KB article:
KB10941: What is the MSTRCtl utility and how is it used in MicroStrategy Intelligence Server 9.x - 10.x