How should I stop users from modifying my data files?

Question

I'm working on a project that is going to replace legacy software on our manufacturing floor. One of my concerns is that currently, config files, script caches, etc are all plain text, stored on the system that the user is using. A lot of this stuff is going to get pushed off to limit access network locations, but things like config files stay local. It's already been an issue with users thinking that they know what they're doing with the system, and modifying the config files. I don't want this happening any more in the new software. How should I prevent this? Encryption? Do some sort of signing/checksum with a database lookup? What kind of features does C#/.NET offer to help me out with this?

UPDATE: Just to address some things that were brought up in comments, every user on the manufacturing floor has admin access to the system they're working on. This isn't likely to change soon as most of the security comes from limiting access to folders on the network, web services, and databases. Permissions would be ideal, I agree, but I have to work in the environment that I'm provided. I plan to bring it up in a meeting that I have with IS to see if this is a possibility, but assume for now that this will be on a system where the user has full access.

Answer 1

This isn't a C# coding issue, it's a system configuration issue. Set up the machine such that the users have normal (non-admin) accounts. Set the file permissions on the config files you're worried about so that anyone (including your app running as current user) can read the config files, but only an admin can write the config files. Finally, don't give the users the admin password. ;>

If your app needs to be able to write the the config files also, you'll have to add code to transition into admin mode within your app, preferably only around the write operation.