Won’t Recognize Updated Upgrade Files on Upload?

I’ve uploaded 2.6.3 almost 4 times and I still can’t upgrade my blog for some reason. It simply doesn’t see that I’ve uploaded new files and still notifies me that I need to upgrade to the latest version. I’ve also tried to upload the Automatic WordPress Upgrade plugin and it won’t show in the plugin list either.

This is really strange. What’s going on? It’s never done this before.