Troubleshooting Network Connections
When Network and Sharing Center displays a red X between your computer and the rest of the network in its status diagram (Figure 5), click the red X to diagnose connection problems.
Figure 5 Preparing to fix a lost connection.
Windows 7 starts network diagnostics, and displays the most likely solution. In this example (Figure 6), network diagnostics reports that the Ethernet cable to the computer is unplugged. Follow the directions and click as indicated to see if the problem is solved.
Figure 6 Windows Network Diagnostics finds the problem.
After plugging in the cable, network diagnostics reports the problem has been solved (Figure 7). Click Close the troubleshooter to finish up.
Figure 7 Problem solved!