Troubleshooting Network Problems : Working with Network Diagnostics

To get started, use any one of the following techniques:

• In the Network Connections window, click the task pane’s Network Troubleshooter link, and then click the Diagnose Network Configuration and Run Automated Networking Tests link.

• Select Start, Help and Support, click Fixing a Problem, click Networking Problems, and then click the Diagnose Network Configuration and Run Automated Networking Tests link.

• In the System Information utility (Start, All Programs, Accessories, System Tools, System Information), select Tools, Net Diagnostics.

• In a Command Prompt window, enter the following command:

  								netsh diag gui

Network Diagnostics operates by performing three different actions:

Setting Scanning Options

To specify which of these actions are performed on which objects, click the Set Scanning Options link in the Network Diagnostics window. You see the Network Diagnostics window shown in Figure 1. You have two ways to proceed:

• In the Actions section, activate the check box beside each action that you want Network Diagnostics to perform.

• In the Categories section, activate the check box beside each object that you want the actions performed on. (Note, however, that not all actions are performed on all objects. For example, the Connect action is performed only on the mail and news server and the Internet Explorer proxy server, if one exists on your network.)

Figure 1. Click the Set Scanning Options link to see the list of Network Diagnostics options.

When you’re done, click Save Options.

Running Network Diagnostics

To start the Network Diagnostics scan, click the Scan Your System link. Network Diagnostics displays the progress of the scan, as shown in Figure 2.

Figure 2. Network Diagnostics shows the progress of the scan.

When the scan has finished, you’ll see the results in a window similar to the one shown in Figure 3. Open the branches to see more detailed objects and the actions that Network Diagnostics performed on them. Look for FAILED in red type to see where possible problems occurred.

Figure 3. The results of a Network Diagnostics scan.

Running Network Diagnostics from the Command Line

You can also run network diagnostics during a Command Prompt session using the NETSH (Net Shell) utility.

For the ping action, you use the following command:

netsh diag ping object

Here, object is a parameter that specifies the object you want to ping. You can either specify an IP address or hostname, or you can use the built-in object names listed in Table 1.

For example, the following command pings the default gateway:

netsh diag ping gateway

For the connect action, you use the following command:

netsh diag connect object

Here, object is a parameter that specifies the object you want to connect with. You can either specify an IP address or hostname, or you can use the built-in object names listed in Table 2.

For example, the following command attempts to connect to the mail server:

netsh diag connect mail

For the show action, you use the following command:

netsh diag show object

Again, object is a parameter that specifies the object you want to display information about. You can use the built-in object names listed in Table 3.

For example, the following command shows information for the network adapter:

netsh diag show adapter