Will “Oracle Express 11gR2” installation mess with the "Opera PMS" software As in the title, I want to install "Oracle Express 11gR2" on a Win7 machine that runs Opera PMS Software (pms for Hotel Management) via Internet Explorer.

I want to write a Python script that will use cx_oracle module. I tried first with "instant client": I put its PATH in windows environment and followed the tutorial, but I still have an import error with cx_oracle module or an error that tells me there is no Oracle application on the computer.

It seems I have to install the Oracle express instead of using the "instant client". But first, I must be sure there will be no dependencies mixing up and messing the system. Can I do that blindly? I can give further info if needed
It's hard to know what new software breaks prior to testing it out on your system, so it's just best to create a Recovery Point on your PC prior to doing so to be safe.  After you create a manual Recovery Point, perform your install, reboot, and test stuff out.  If you feel dependencies were affected and you're unable to resolve them, you can always recover your system back to the recover point, effectively rolling back the installation (and any damage it caused).