The Windows Installer Service could not be accessed

got one of those error messages?
"The Windows Installer Service could not be accessed"
"Error - 1608: Unable to create InstallDriver instance"

many pages out there explain how to solve this problems by running too deep into DLLs and Registry keys ... people sometimes forget some basics steps that most of the cases solves those problems:

1) check the windows service "Windows installer" is running

also note that InstallShield requires the DCOM service to be running too.
otherwise it will give this other error message:
"Error - 1608: Unable to create InstallDriver instance"
so, as a 2nd step:

2) check the windows service DCOM is running

or run this cmds:

NET START MSISERVER
NET START DCOMLAUNCH

goodluck