I had a funny distance debugging experience while traveling in Boston. We were staying with in-laws who had a high-speed connection, but had it hooked up to only one computer. I decided to go into my old office in Somerville, and while I was there, my wife called because she wanted to hook up her computer so she could check her email. She told me that it looked like a cable modem (which it was), so I knew from experience that generally they are relatively simple to hook up to. You don't need a username and password most of the time since it is lan-style connection (i.e. plug in your ethernet cable and go) rather than PPPoE or something else more complicated. However, I also knew, from a very frustrating past experience, that the cable modem learns your MAC address, and so you can't just disconnect one computer and hook up another, you have to turn the modem off and back on again. Here is a transcript of our conversation:

Me: Plug the ethernet cable into your computer.

Wife: Okay, done.

Me: Now turn the modem off and back on again.

Wife: So I should just hit the on/off button on the top and then hit it again?

Me: Yeah, wait 15 seconds or so before turning it back on again.

Wife: Okay...now what?

Me: (long-winded description of configuring dhcp on Mac OS X)

Wife: It won't give me an IP address

Me: Hmmm

I was pretty much stumped and chalked it up to some system I hadn't seen before or which required a password as some cable services do. . Later on when I got home, I looked at the modem and saw the "on/off" button. I realized then that it was actually the "standby" button, which wasn't what we needed at all. The modem has no on/off button; you have to unplug and replug it.

It's funny because at the time I thought, "Gee, these things almost never have on/off switches since it saves 3 cents. This must be a model I've never seen before." Instead of asking better questions like "are all the lights off now?" (they wouldn't be in standby mode, the standby light would be lit). To me it's a classic example of falling into a trap of assuming that the information being given by the remote person (and my wife is very technically savvy, so I had no reason to doubt her) is completely accurate, rather than relying on the observables to verify information. I had done everything right, except for asking her to push a button that didn't exist.