As in, change a texture to xnb or compiling XNA code? The texture to Xnb can be found via a simple google search 
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Boffin
DerpoTheMagnificent
Right...xnb, not xna. And I tried searching, and this is the only thing I could find. https://xnacontentcompiler.codeplex.com/
Boffin
That's the one I use, I just compiled the code
DerpoTheMagnificent
Darn, I can't get it to work. When I try to run it, it asks me to choose an application to open it with, my only option is Visual C# Express 2010. When I select it, it asks me for a registration key. But when I click the link it gives me to get the key, it says the page does not exist. I don't suppose that's anything you know how to help with...
Boffin
That's probably because you haven't bought VS, I thin I've got the express 2012 version, but I used to get the same issue with 2010. Nothing, unfortunately, I can help you with.
DerpoTheMagnificent
Well crud. Would you be able to compile the files for me then? I don't have them now, I'm still working on them.