Fixing networking problems in Windows 2000. Before tackling the OS (operating system) side of the networking equation, check the physical components (cables, power adapters, modems, printers, routers, and switches) that make up your network. If you can’t access a printer in another room, it certainly could be an OS issue, but it could also be as simple as a disconnected cable. Save yourself time and trouble, and eliminate the obvious possibilities first. Troubleshooting Basics Most Win2000 diagnostic and troubleshooting tools operate from the command line. To access the command line, click Start and then select Run. In the Run dialog box, type cmd and click OK or press ENTER. To determine whether Win2000 can talk to your computer’s NIC (network interface card), perform a basic loopback test. Bring up the command line, type ping 127.0.0.1, and press ENTER. When the test results display, the ping statistics should show 4 packets sent, 4 packets received, and no packets lost. Any other response indicates a problem with your NIC, or with the drivers that allow Win2000 and your NIC to communicate. Check the NIC manufacturer’s Web site for updated drivers. Install the updated drivers and run the test again. If you still have problems, try pinging your NIC’s IP (Internet Protocol) address. To do this, you must first determine what that address is. Bring up the command line, type ipconfig, and press ENTER. The command result will list your NIC’s IP address, Subnet Mask, and Default Gateway. Using the listed IP address, perform another ping test. You should once again see a response with all packets sent and received, and no packets lost. If there are any lost packets, disconnect the Ethernet cable from your NIC and perform the ping test again. If there are no lost packets this time, then the Ethernet cable or the network device to which the cable connects is having problems. If the ping test continues to fail, you may have a bad NIC. Replace the NIC and check your networking connectivity again. If your NIC passes with flying colors, but you’re still having problems, reissue the ipconfig command, and check the IP address it reports. It should be a valid IP, either manually assigned by you or automatically assigned by your router. If the IP is 169.254.xxx.xxx , it indicates that your computer was unable to be assigned an IP from a DHCP (Dynamic Host Configuration Protocol) server, either on your network or from your ISP (Internet service provider). You can try to force a new IP assignment from your DHCP server. Bring up the command line, type ipconfig /release, press ENTER, and then type ipconfig /renew. After you issue the renew command, the command results will list your IP address, Subnet Mask, and Default Gateway. If you still do not receive a valid IP address, check how your DHCP server is configured. In most cases, your DHCP server is your router. If so, check the instructions for your router to confirm that it is configured correctly and operating correctly. If your ISP supplies your DHCP service, contact your ISP for assistance. The last test is to ensure that you can access your DNS (Domain Name System) servers. To do this, you need to know your DNS IP addresses. Bring up the command line, type ipconfig /all and press ENTER. Look through the results for a DNS Servers entry; there may be multiple IP addresses listed. Use the command line to issue a ping command for each IP address. The results for each should be the same as other ping commands; all packets sent, and no packets lost. If your system passes this test, you know that you can access your DNS server as well as host computers on the Internet. If your system fails this test, it can indicate a problem with your ISP’s network. Contact your ISP to resolve the problem. Successful completion of the above series of tests ensures that your computer can communicate with your NIC, and that your NIC can communicate with devices on your network and the Internet. At this point, you have successfully eliminated most hardware and driver issues as the cause of your network problem. Network Services Win2000 includes many services that make it easy to use a home network. We will concentrate on the basic File And Printer Sharing services. These services run as a peer-to-peer network, meaning no central server is necessary. Instead, each computer on the network can make services, such as file sharing, available to other devices on the network. In order for Microsoft’s peer-to-peer network to work correctly, you must ensure that computer and workgroup names conform to specific Microsoft naming conventions. Computer names must be unique; no two computers on your network may have the same name. On the other hand, workgroup names must be the same. Computer and workgroup names should both be all uppercase letters, with no spaces, no special characters, and no more than 15 characters in length. To check or change your computer’s name, right-click the My Computer icon on the Desktop, and select Properties from the pop-up menu. Click the Network Identification tab to see your Computer and Workgroup names. Click the Properties button. If needed, enter a new name in the Computer Name field. In the Member Of area, make sure the Workgroup option is selected. Win9x/Me/2000 use WORKGROUP as the default workgroup name; WinXP uses MSHOME. You can assign a name of your choice, as long as all computers use the same name. Click OK and reboot. File And Printer Sharing Every computer name on your network must be unique, but every computer you want to access on your network must share the same workgroup name. File And Printer Sharing is used more than any other service in most home networks. When it is working, you can access shared folders through My Network Places, or by using mapped network drives, via the Desktop or the Windows Explorer interface. When it isn’t working, you may see cryptic error messages, or you may notice that no shared items display in My Network Places, or that you can’t access shared printers. You must enable File and Printer Sharing before you can create shared resources on your computer. As always, start with the basics. Is File And Printer Sharing turned on for the device you want to access? Someone may have turned this option off when using another computer for processor- or graphics-intensive applications, such as games or video-editing. In many cases, restarting the Sharing option will solve the problem. On the computer that hosts the shared folder (or printer), right-click My Network Places and select Properties from the pop-up menu. Double-click the icon for your Local Area Connection and click Properties. Make sure that File And Printer Sharing For Microsoft Networks is listed and has a check mark next to it. While you’re at the host computer, verify that the folder you want to access is actually marked for sharing. Right-click the folder and select Properties from the pop-up menu. Click the Sharing tab. Make sure that the Share This Folder option is selected, and that a Share Name has been entered. Click the Permissions button to view the Share Permissions and make any necessary adjustments. Security we are concerned with the use of local users and groups to allow simple peer-to-peer file sharing using Microsoft’s built-in network clients. These simple user security settings can cause unexpected problems when you attempt to access a shared folder or printer from other Windows computers on your network. The most common error starts with a dialog box that asks for a password in order to access a shared folder or printer. You provide a known good password, but it is rejected, and you are asked to re-enter the password. The reason for this error is that Win2000 expects both the username and password to match up to a user defined in Users And Groups. When you attempt to access a share, your currently logged in username and password are sent to the Win2000 computer that is hosting the share. If the username and password don’t match up, Win2000 asks for another password but not another username. Even if you provide the correct password, your computer may not be supplying the correct username. When you try to access a shared resource, Windows 2000 will expect both a username and a password. To fix this issue, make sure that any individual you want to have access to a share on a Win2000 computer is given a local username and password on that computer. You must log on to the host computer as an Administrator to make the following changes. Click Start and then select Settings and Control Panel. Double-click the Users and Passwords icon. Click the Users tab, and click Add. Enter a username that matches the Windows logon name on the remote computer (the one that will be used to access the computer that hosts the share). Click Next. Select a type of account for the user. Remote users usually do not need to be Administrators or even Standard users. For simple file access and printer sharing, selecting Restricted user will work nicely. Click Finish. The Ipconfig /all command can provide important information about your network connection, including your DNS (Domain Name System) and the DHCP (Dynamic Host Configuration Protocol) servers you are using. Another common error is, “ is not accessible. Access is denied.” This error message can crop up when the computer that hosts the shared folder or printer, or the printer itself, has been turned off or when there’s a physical network problem. Another common problem that can produce this error are shared item security settings that do not allow access for a particular user. This is a bit different than a share’s permissions; it is the folder’s permissions on the host machine. To correct this error, log on to the host computer with an account that has administrator privileges. Right-click the problem folder and select Properties from the pop-up menu. Click the Security tab, and scan the list of names to ensure that the individual’s username, or a group the individual belongs to, is listed. If neither is listed, click the Add button. Scroll through the list of Users and Groups until you find the individual’s username or a group the individual belongs to. Highlight the name, click Add, and then click OK. (Remember, if you select a group, you are giving all members of that group access to the files in the folder.) Back in the Security tab, highlight the name you just added to the list. The Permissions box will display the rights of that user to access the folder. For general read/write access, there should be a check mark in the Allow column next to Read & Execute, List Folder Contents, Read, and Write. Printer Sharing If you can’t access a shared printer that you could previously access, and you’ve eliminated the obvious possibilities, there may be a network problem. Follow the troubleshooting tips listed above. If this is the first time you’ve attempted to access a network printer, make sure that it is set up correctly, both on the host computer and the computer you are using to access it. On the host computer, the printer should first be configured normally, as a local printer. It must also have drivers installed for all of the operating systems that will be used to access it. On the host computer, click Start and select Settings and then Printers. Right-click the printer you want to share and select Properties from the pop-up menu. Click the Sharing tab, then click the Shared As button, and enter a name for the printer. Click the Additional Drivers button. Put a check mark next to any of the listed OSes you will use to access the printer and click OK. Follow the on-screen instructions to install any missing drivers. On the computer you are using to access the shared printer, use the Add Printer wizard to set up a new printer. Click Start and select Settings and then Printers. Double-click the Add Printer icon and follow the on-screen instructions. Be sure to select Network Printer as the type of printer you wish to install.