Connecting two computers

By George Skarbek - 5th April 2005

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Computer GuideQ: I am trying to connect a laptop to a desktop computer using an Ethernet cable and both computers are running Windows XP but I am not able to see either computer from the other one. What do I have to enable to do to make them see each other so that I can share files between them?

A: This is a big topic and I can only give you some basic pointers of where to start. With two computers it is much harder to determine where the problem is than with three or more. Below are the basic steps that you should follow to solve this problem. The first step is to turn off all firewalls. A firewall will naturally block all incoming traffic from the other computer and therefore there will no response of any sort.

Next ensure that you have the correct cable. If you are using a hub then you must have two normal Cat 5 cables connecting the computers to the hub. However, if you have just one cable connecting both computers then you must use a cross-over cable otherwise there cannot be any response from either end.

Assuming that the above points are correct you must then establish if both network cards and the cables work before investigating sharing of resources. This step is best done from a DOS box using the PING command as does not require any permissions on the remote computer. Open a DOS box by Click on Start, Run and type CMD then type IPCONFIG to view the computer’s IP address. Then on the other computer, from the DOS box type PING 192.168... where the numbers that entered represent the IP address displayed on the other computer. If you do not receive a reply then the problem almost certainly has nothing to do with Windows, permissions or networking, but it will be a hardware problem. Either the cable or one network card is faulty.

Assuming you receive a reply then continue the diagnostic from the DOS box. To see what resources the other computer is sharing type NET VIEW \\ComputerName where ComputerName is the name of the other computer. DOS is not case sensitive and if you do not know the name then click on Start, Settings, Control Panel, System and click the Computer Name tab. If the reply shows the other computer but nothing else then you must Share some folders or in order to have access. This is done from Windows Explorer by right-clicking on your folder and select Sharing. If Permission Is Denied is shown, then you must alter those settings.

If you still cannot communicate between the computers then I recommend that you re-install the NetBEUI protocol on both computers. I have found that this has often fixed obscure networking problems.

NetBEUI is a tiny and very reliable protocol but for some inexplicable reason is not automatically installed in XP. Installation is relatively simple. From the XP CD locate the ValueAdd\Msft\Net\NetBEUI folder copy nbf.sys into the Windows\System32\Drivers folder and then copy the file netnbf.inf into the Windows\Inf folder. Note that these folders may be hidden so you may have to alter Windows Explorer to show hidden files from Tools, Folder Options, View. Finally open network connection properties and on the General tab click Install, Protocol, Add and select NetBEUI.


Q: Does adding a second hard drive to a PC using Windows XP offer any sort of virus protection? i.e. the thinking being that a virus problem might only affect the primary hard drive? Would the situation be different if the second drive of a system was an external drive i.e. something that utilised a mobile rack for instance, so the drive could be physically separated from the primary drive?

A: Adding a second hard drive will not stop an incoming virus but the extent of the damage depends on the virus. A destructive virus will most likely only wipe drive C: so having a second drive as a backup is a very good idea.

Having a removable hard disk will give you more security. If a non-detected virus is copied to the external drive, it is not likely to be activated there and if scanning later with an updated AV product, it is likely to be found and removed.

For all of my clients I recommend a second physical hard disk, primarily for backup purposes with automated backups. Performance is also improved by placing the Windows swap file onto the second hard disk as this will enable both read-write heads on both drives to operate simultaneously.

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