If this is for anything other than a mild 'stop people fiddling' security then why bother. It would take someone only a few minutes to pull the key and the code you use from the assembly.

XNAtticus:

I need a way to encrypt these files

What's your question?

XNAtticus:

recently added and doesn't seem to work

How can you tell?

The ZMan:

It would take someone only a few minutes to pull the key and the code you use from the assembly.

It takes someone only a few minutes to pick a lock, too, but I still lock my doors - because most people don't pick locks.

CDarklock:

XNAtticus:

I need a way to encrypt these files

What's your question?

XNAtticus:

recently added and doesn't seem to work

How can you tell?

The ZMan:

It would take someone only a few minutes to pull the key and the code you use from the assembly.

It takes someone only a few minutes to pick a lock, too, but I still lock my doors - because most people don't pick locks.

I know it doesn't work because it will save my game and I can go grab the file, open it, and it's still viewable as a basic XML document.  I want it to look scrambled when I open it somehow (basically like changing "Test" into "asihdoiahs" or something).  How do I do this?  My friend built a basic C# app that did this although I'm not sure what he used to do it.

If they're that serious about going into my assembly, pulling the code, and cracking it, I'm fine with that.  But most general home users won't bother with that (granted there won't be loads of people playing).  I'd just feel better with it somewhat protected.

XNAtticus:

I know it doesn't work because it will save my game and I can go grab the file, open it, and it's still viewable as a basic XML document.

Then File.Encrypt() is not what you want. The account which encrypts the file can still view the file transparently; only other accounts can't view it. Use something from System.Security.Cryptography instead, or create your save process under alternate credentials.