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 Troubleshooting (continued)

In Figure 7 we see this showing that IRQ 5 is used by “PCI Steering,” and that out of only 15 IRQs available, only one -- IRQ 12 -- is free. This is also a good chance to determine whether Windows is correct in telling you there are no conflicts with your NIC.  In the case of Figure 7, the NE2000 compatible NIC brings up a Resources screen that says it also is trying to use IRQ 5, but that IRQ 5 is not in conflict.  We know from this other screen that there actually is a conflict.  It’s a good guess that this is the cause of the red “X” in the NE2000 NIC in System Properties. 

 Figure 7: How to determine the IRQs and I/O ranges in use on your computer. 

 If your NIC has a resource conflict that isn’t set in hardware, but is in use by another device, it will usually have an asterisk by it.  In System properties highlight your errant NIC, click Properties, and click on change settings.  Try different settings until you get resources that don’t show a conflict. 

This doesn’t always solve your problem.  For example, if there is a pound mark by a setting, it means the setting is controlled in hardware.  If a resource set in hardware is in conflict with another of your devices, one possible solution is to take your NIC out of your computer, and move around a jumper or two.

 If your documentation for the NIC doesn’t tell you what to do, use that bright light and magnifying glass to read the tiny printing on the NIC for instructions.  Next, look for jumper(s).  A NIC jumper is a tiny plastic rectangle that sits on top of a pair of metal posts.  You will find it easy to move the jumper to a different pair of posts by using the needle nose pliers.

 Another problem could be that all the IRQs or I/O ranges are all already in use.  Here is a way to fix it.  You need to reboot your computer and go into Setup -- the setup that comes before the operating system loads.  On most computers you hit the delete key to do this. 

 In setup, choose “integrated peripherals.” 

 You need to make a table of IRQs and I/O ranges by going methodically down the list of devices.  First, click on each box with a plus sign, which displays all devices under that category.  Then start at the top and check properties of each device, and write down what you find.  These are all IRQs and I/O ranges your NIC is not able to use.

 What if Windows can’t change the IRQ and you don’t find a jumper you can set it with on the board?  Your problem may be that the IRQ is set in a flash ROM chip on your card.

 Figure 8:  How to find out what COMs are in use on your motherboard.

 What if every IRQ and/or I/O range is already in use?  If you have lots of devices attached to your computer, this might happen.  A way to make room for your NIC is to disable any users of your scarce IRQs or I/O resources that you don’t use.

 For example, if you have just one modem and no other devices besides a mouse attached to your serial ports, you don’t need to use  two of the four serial ports that most motherboards allow.  Your mouse will normally be using the first serial port (COM1).  You can check to make sure what COM your mouse uses with the System Properties Device Manager.  You modem will usually use COM2, which you also can check on Device Manager.  If any other serial ports are in use, you will find them listed in Device Manager.  Figure 8 shows one way to check what COM your modem uses.

 If you are using less than four COMs, then you can safely disable a serial port on your motherboard.  To do this, reboot your computer.  At the very beginning, change your BIOS by going into setup (usually by hitting the delete key.  Go to the Integrated Peripherals menu.  Pick the last serial port on the list that is shown using an IRQ and I/O resources.  Write these down, then disable that port.

 Now go back to setting up your NIC -- and use the resources that serial port you just killed used.

 Another problem may be that you have a plug and play NIC that won’t plug and play.  This may be the fault of your motherboard.  Go back into setup, and this time go to the PNP/PCI Configuration menu.  If this menu doesn’t exist, your motherboard probably doesn’t support plug and play.  If it does exist, check to see whether plug and play is enabled for your ISA and PCI slots.  If not, set them to plug and play.

 If this doesn’t fix your NIC, you have one more option.  Guess what, when Windows says your NIC is using certain resources, it may be wrong!  Sometimes a NIC won’t let Windows reset its resources, and instead of honestly telling you this failed, shows you the resources you set in Device manager instead of the real resources your NIC is using. 

 Here is where we learn about flash PROMs!  Your NIC may have a programmable memory chip (PROM).  You can use it to set the IRQ and/or I/O settings you need.

 The nice thing about PROMs is that once you program them, they stay that way forever, regardless of whether they have power, unless you choose to reprogram them. However, often Windows can’t reprogram it for you.

 So how do you program the PROM?  Read any files named README on your installation disk to find out how to do this.  It may ask you to reboot your computer into safe mode to run the program to reprogram your NIC.  If you have a DOS boot disk, it’s often the easiest way to do that.  However, if you are new to computers, you probably don’t have DOS in you tool kit.

 Here’s how to get into safe mode.  Shut your computer down.  Then before Windows begins to boot, hit F8.  This gives you a safe mode menu.  Choose the DOS mode your installation disk’s README file tells you to use, and then run the installation program so you can choose an IRQ and/or I/O resources that won’t conflict with anything else.

 If  F8 doesn’t work, it’s because someone or some program decided to make that computer more secure by turning off the boot keys feature.  If you are running Boot Magic, you must first have set it up so that Windows is the default operating system (the one that boots if you do nothing).

 If you aren’t running Boot Magic, your msdos.sys program may have disabled boot keys.  Instructions on how to enable or disable the boot keys are in Section 1, Chapter 2.

Can’t ping your NIC from across the network? 

 After you get done saying bad words, ping the NIC that didn’t answer from inside your computer.  If you are still able to ping that NIC from inside its computer, there probably is nothing wrong with your NICs.  So your suspects for any trouble are either you set up your IP addresses wrong, netmask wrong, or there is a problem with the patch cord or the port on the hub. 

 Check to make sure that you set up the TCP/IP settings exactly as described above.  Now is not a good time to improvise, OK?

 Next, check the cabling and hub.  Here is where any pretty lights on the NICs and hub come in handy.  Each NIC, if it is alive, should have a green light.  Each port on the hub that has a live NIC attached to it should also show a light.  You may also have extra lights that blink when you send data (such as a ping) over your network; and for collisions (too much data interfering with each other).

 If your NIC has a light shining, and you can ping it from inside your computer, it probably has nothing wrong with it.  Look at the port it connects to on the hub.  Is that light on?  If it isn’t, you should suspect the patch cable.

 First, make sure your patch cable is properly connected.  Take it off and attach it again.  When the connector properly seats, it makes a click.  If you don’t hear the click, try pressing it in a little harder.  If this doesn’t work, if another computer is working over the network, try trading cables.  If this fixes the problem, you probably have a bad cable.

 If this doesn’t work, try attaching the cable to a port on the hub that was attached to a computer that was able to communicate over the network.

 If none of your computers can ping any others, yet a crossover cable connecting two NICs works, it’s time to suspect the hub.  This is where the crossover cable comes in handy.  Directly connect two computers with the crossover cable.  If they can talk to each other, you have something wrong with the hub.


 If setting up your Win98 network made you throw fits, give up on calling yourself a hacker.  Use this book for a fly swatter or to shim up a table with uneven legs.

 If you discovered that building a network was fun, you are the kind of person who could become a systems administrator or computer security expert.  Hang on to your hat!  You will soon discover that Unix type operating systems are much easier to network. I’m betting that having succeeeded at networking Windows computers, you will work out how to add other operating systems on your own.  And once you are able to network many different operating systems, you will possess a hacker laboratory that will open the doorway to the Uberhacking skills of your dreams.

Back to building a Windows hacker lab --->>

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