If you came to Windows 7 from Windows XP, you may
have come across the latter’s network repair tool that did an okay job
of repairing connectivity problems because most networking problems can
be resolved by running the repair tool’s basic tasks: disconnecting,
renewing the Dynamic Host Control Protocol (DHCP) lease, flushing
various network caches, and then reconnecting.
Unfortunately,
the repair tool would all too often report that it couldn’t fix the
problem, which usually meant that the trouble existed at a level deeper
in the network stack than the repair tool could go. In an attempt to
handle these more challenging connectivity issues, Windows 7 comes with a
Network Diagnostics tool (borrowed from Windows Vista) that digs deep
into all layers of the network stack to try to identify and resolve
problems. Windows 7 gives you several methods of launching the Network
Diagnostic tool:
Right-click the notification area’s Network icon, and then click Troubleshoot Problems.
In the Network and Sharing Center, click the Troubleshoot Problems link.
In the Network Connections window, click the broken connection, and then click Diagnose This Connection.
Note
To open the Network Connections window, select Start, type connections, and then click View Network Connections.
When you launch the
diagnostics, Windows 7 invokes the new Network Diagnostics Framework
(NDF), a collection of tools, technologies, algorithms, programming
interfaces, services, and troubleshooters. The NDF passes the specifics
of the problem to the Network Diagnostics Engine (NDE), which then
generates a list of possible causes. For each potential cause, the NDE
launches a specific troubleshooter, which determines whether the aspect
of networking covered by the troubleshooter could be creating the
problem. For example, there are troubleshooters related to wireless
connectivity, Transport Control Protocol (TCP) connections, address
acquisition, and many more. In the end, the troubleshooters end up
creating a list of possible solutions to the problem. If only one
solution can be performed automatically, the NDE attempts the solution.
If there are multiple solutions (or a single solution that requires user
input), you see a Windows Network Diagnostics dialog box similar to the
one shown in Figure 1. Click the solution or follow the instructions that appear.
