If you can take the person aside and ask them in the right way, they can tell you everything about what's not working - both what is blocking them today, and al

If you can take the person aside and ask them in the right way, they can tell you everything about what's not working - both what is blocking them today, and also the smaller problems that have been haunting them for a while. The first part is to try to learn from them - how do they normally use the system, what isn't working today, and any errors that are (or aren't) showing up. The hard part in this is in actually wanting to help the person and/or solve the problem, and not getting caught up in your own superior ability to avoid the problem. The first step to good troubleshooting is checking your own ego at the door.