I help (unattended) two family members and a friend as an "IT Guru". They have an iMac identical to mine, a Macbook Pro, and a Dell PC laptop. I have no trouble connecting to them, and they can connect to each other, but they can't connect to me -- which puts the problem squarely on my shoulders. I'm doing something wrong in my system, but I have no idea what it is.
Any help?