Direct Cable Connection Problem

I am trying to connect computer “A” to computer “B” via a direct cable connection. When “A” is set as the host, I am able to share files, but when I switch the settings and choose “B” as the host and “A” as the guest, a window pops up that says, “Cannot Find The Host Computer”. Help me, pleeeeease.

For $25 you can get a USB cable which networks both computers. It is much faster and they are peer to peer. I would forget about that DCC which is a pain.