Ethernet not working

[ElDiabloConCaca]

Well, this may have something to do with a basic understanding of how networks operate. When you connect from one computer to another, you either use an account that exists on the computer you're connecting to, or, in some cases, you may be allowed to connect as a "guest."

So, when you connected from one computer to the other for that file transfer, you may not have used a user account that has permissions to access certain places/files/folders. Let's say on one computer, you have an account named "bob" who is an administrator. On the other computer, "sally" is an administrator. If you hop on bob's computer and connect to sally's computer using bob's credentials, then bob won't have access to sally's stuff... why? Because that would be insecure. What you really want to do in this scenario is hop on bob's computer, connect to sally's computer, and use sally's credentials to log in (because sally's computer knows nothing of the user "bob", see?).