Easy Troubleshooting with Network Diagnostics and WNTIPCFG Networking Diagnostics for Windows to the Rescue Joseph Moran
When you experience a connectivity problem — say, if you can't reach a Web site or send and receive e-mail — it's usually safe to assume that your system's connection to the Internet has somehow failed.
When this occurs, you can usually determine the exact nature or location of the problem with a series of ping tests. But tucked away into Windows XP is a built-in utility called Network Diagnostics that can save some time and effort by automatically scanning various aspects of your connection with a single click.
You can access Network Diagnostics from within the Start Menu's Help and Support option. From there click the Use Tools ... link under Pick a task, and then click Network Diagnostics from the list of tools. (Another way to get there is to enter netsh diag gui from the Run > menu.)
Network Diagnostics scans a fairly wide range of stuff by default, and much of it isn't especially pertinent for basic Internet connection troubleshooting. So before doing a scan, it can be helpful to pare down the areas Network Diagnostics will look at, which will result in less irrelevant information to wade through once the report is generated.
After clicking Set scanning options, find the Categories selection and make sure only the following items are checked: Mail Service (only useful if you use Outlook Express, because this option unfortunately doesn't return a result with any other mail client), Domain Name System (DNS), Dynamic Host Configuration Protocol (DHCP), Default Gateways, and Internet Protocol Address.
When you click Scan your system, Network Diagnostics will scan all the items specified, a process that should take between 30-60 seconds and result in a PASSED or FAILED for each item once the entire scan is complete. If any of the items can't be reached or if the response is intermittent, it will be marked FAILED indicating that it's the likely source of the problem.
For example, if DHCP Servers or Default Gateways fails, it means your system can't access the router, a problem that's typically fixable by rebooting the router. On the other hand, a failure only under DNS Servers indicates that either the DNS servers are down or your Internet connection to them is.
When a connectivity problem is on your network rather than beyond it, it can often be cleared up by the simple act of releasing and renewing a system's DHCP-assigned IP address. There are a couple of ways to do this — one is to right-click the network connection's Windows tray icon and then choose Repair (this doesn't just release/renew the IP address, but also disables and then re-enables the entire network connection for good measure).
Ditching IPCONFIG and Going Graphical with WNTIPCFG
The Repair function is a quick and easy way to refresh your IP address, but it doesn't display any IP configuration information (which you may sometimes want to see) while doing so. If you want to release/renew your IP address, but also have the opportunity to view your settings before or after the process, you must use the IPCONFIG utility, which is only accessible from a command-line window.
If you have an older version of Windows, you may recall that there used to be a tool called Windows IP Configuration — perhaps better known by its program filename, WINIPCFG — that provided an easy-to-use GUI for releasing and renewing IP addresses.
Alas, you only get WINIPCFG with Windows 95/98 and Me, while Windows XP and its progenitors (2000 and NT) have always had to make do with the less convenient command-line version. But you can retrofit your XP system with a graphical version of IPCONFIG called WNTIPCFG, which you can download for free here.
WNTIPCFG's installation wizard puts the utility by default into a Program Files/Resource Kit folder (it was originally part of the Windows 2000 Resource Kit) and it doesn't create a Start menu folder or a program shortcut, but you can run it from the install location or create your own shortcut for easier access.
WNTIPCFG works pretty much the same as WINIPCFG did — just select the network adapter you want from the list of installed adapters (note — the scroll buttons are so small they don't even have arrows, but they still work). This will display basic IP info (address, subnet mask, and default gateway) for that adapter, and you can click the appropriate buttons to release and renew its address. Like the /ALL option in IPCONFIG, the More Info button expands the view to show additional data such as when the address lease was assigned and will expire.
Periodic connectivity problems are inevitable for most Windows users, but hopefully Network Diagnostics and WNTIPCFG can make identifying and fixing them a little bit easier.
Joe Moran is a regular contributor to PracticallyNetworked.
