Same System Setup NIS/NFS - But Facing Issue

System Setup: NIS/ NFS – Home directory is also configured.
Problem: when users invoke the source <NFS-sharepath>/script_location. One system it is invoking properly but on another system, it says command not found from the same user id.
NOTE: So, I can say there is no problem with the application side, some problem has been found only on the system side.
How I troubleshoot
System A(system have problem)
System B(System is working fine)
1)#which command_name
Command is not found
2)PATH is not properly set. So, I have set the proper PATH for environment variable
3)Then I have tried after that also I have faced the same is shell script, so I have execute in VERBOSE mode.then I have found while run the shell script I got the error message particular command not found.
4)while checking I have directly invoked that  single command (then also I  faced the same problem).
5)So, I have check that command is binary file or script while checking it is the ksh shell script. In this machine, ksh shell script is not installed compare to another system. Once installed the problem get solved.
#which command_name
Command is found