Troubleshooting With Network Diagnostics and WNTIPCFG

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
(only useful if you use Outlook Express, because this option
unfortunately doesn’t return a result with any other mail client), Domain Name
(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).

Ditch IPCONFIG and Go 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

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.

Adapted from, part of the Network.

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