Sometimes you'll run into problems in the process of setting up or maintaining your network, but they shouldn't be a permanent feature. The most common problems occur during the setup process, when you're not yet familiar with the networking process. Note that this section deals with things gone wrong, not the network setup process. When you work with your network, especially when trying to solve problems, keep these things in mind. Only plug and unplug network devices with the power off to avoid damaging your Mac.
Network hardware can go bad, but it starts bad more often than it goes bad.
If you have problems with hardware that was previously working, troubleshoot your software first. Reinstalling the network software is the most common solution to nagging network problems. Use the most current versions of your network software to avoid conflicts with other software. Check your product manufacturer's web site for updates regularly, especially if you have a new product that might have bugs in the early versions. No, you're limited to 10 users accessing your Mac at a time.