Reader Bill Robertson would like to make his Mac stick out its tongue and say “Ahh.” He writes:
Parts of my network are acting up and I’d like to use Apple’s Network Diagnostics tool to help troubleshoot the problem. But I can’t figure out how to launch it. I’ve seen a button that starts it in Safari when I can’t connect to the Internet but otherwise nothing. Where is it?
The Network in Network Diagnostics gives you a hint. One way to launch it is to open the Network system preference, click the Assist Me button, and, in the sheet that appears, click the Diagnostics button. Network Diagnostics will launch in short order. (Clicking the Assistant button next to the Diagnostics button launches the Network Setup Assistant.)
The other way is to follow this path:
/System/Library/CoreServices
and double-click the Network Diagnostics icon.