Summary of classic faults in Internet cafes (II)

1. The network cable test is correct and the machine cannot access the Internet.

Fault performance: There are several machines in the Internet cafe, and there is no problem with the network cable. The network tester is used for testing and the communication is normal. The machine operating system is Windows XP. Switch to the DOS prompt and run the Ping command to check the connectivity with the Internal Gateway of the Internet cafe. Serious packet loss occurs. After the crystal head is cut off and re-built, the fault still persists. After the NIC of the computer is changed, the problem still cannot be solved, and the ports connected to the switch are also changed.

Fault resolution: when the network cannot be connected, especially for networks using twisted pair wires as the network transmission medium, check the length of twisted pair wires first. Theoretically, the transmission distance of cat5e shielded twisted pair wires is 100 meters, but the actual transmission distance is no more than 95 meters. When we purchased twisted pair wires, many profiteers used three types of cables to impersonate five types of cables, resulting in a large reduction in the transmission distance of twisted pair wires. When wiring, we must note that the transmission distance should be controlled within 80 meters as much as possible. A common network cable Tester for testing twisted pair wires can only test whether the physical connections of twisted pair wires are connected and whether the network cables can be used normally.

Fault Comment: In this case, although our twisted pair wires can be used normally through the network cable tester test, this can only test that the circuit part of the twisted pair wires is connected, when network signals are transmitted through twisted pair wires, signals over one hundred meters may decay or even disappear. Therefore, when wiring, we must ensure that the distance between the two individual nodes is not more than 90 meters, and when purchasing a twisted pair, try to choose a genuine cat-5e twisted pair, to protect the quality of network transmission.

2. Use the Deepfreeze software to restore Windows XP, and the system files are often lost or damaged.

Fault description: Windows XP is used in the internet cafe machine operating system, and the file system adopts the FAT32 format. Because the recovery genie software is used to protect the hard disk, it is often damaged by the QQ tail virus. Therefore, the Deepfreeze restoration software is used. In the use of the operating system, system Dll files are often lost or damaged. This is not the case if the Deepfreeze restoration software is not installed on the machine, in addition, some machines may have blue screens.

Troubleshooting: for Windows XP and Windows 2000 operating systems, to use Deepfreeze to restore software, you must use the NTFS file system to avoid problems. The Deepfreeze instruction requires that the NTFS file system be used.

Fault comment: Before using a new software, please carefully read the software environment required for running the software. For systems that have used the FAT32 format, we can use the Convert command to Convert the file system from the FAT32 format to the NTFS file system without breaking the bad hard disk data. The specific operation is to enter Convert X:/fs: ntfs at the DOS prompt of the operating system and press Enter. X indicates the partition drive letter to be converted. After the command is run, the system automatically converts the partition to NTFS format after the machine is restarted.

3. The desktop icon of the operating system disappears.

Fault description: in Windows XP, the host is running and automatically restarted. After restarting and entering the operating system, it is found that only the taskbar is on the desktop, and the icons on the desktop disappear. The hard drive lamp also stops working, and press Alt + Ctrl + Del to bring up the task manager, view the process of the task manager, and you can see that there is an Explorer desktop process in the system process. On the desktop, right-click the menu. View the settings of the taskbar. The system uses the Windows classic Start Menu.
Fault resolution: For Windows operating systems, you can hide the desktop icon in right-click desktop settings or display settings. Right-click the desktop and you can bring up a menu. In this way, you can view the right-click menu. In the "arrange icon" submenu, the "show desktop icon" option is displayed, we can see that this option is not activated. After the "show desktop icon" option is activated, the desktop icon appears.

Fault comment: When a fault occurs, do not think too complicated. The desktop icons all disappear, which is a big problem in our impression, but we can see that the taskbar and right-click the desktop can be used. With the available resources, you can quickly find the fault. In addition, if the Explorer process is disabled, the desktop icon disappears and the taskbar does not exist. However, you can use Alt + Ctrl + Del to call out the task manager, run the "Explorer" program to display the taskbar and desktop icons.

4. full-duplex NICs cannot work in MB full-duplex status

Fault performance: the Internet cafe operating system is Windows 2000. In an operating system optimization article, we can see that the full-duplex network adapter is 10-MB adaptive network adapter, and the default working status is Auto. In the hardware manager, find the NIC device and click its properties. In the "advanced" option

After the transfer rate is changed to 100 Mb Full Mode, the NIC will work in a Mb environment. However, after the optimization operation, the computer cannot access the Internet.

Fault resolution: Most of the NICS used in our Internet cafes are 10-100Mb adaptive NICs. The network adapter automatically adjusts the network transmission speed according to the network transmission status. Some of our switches do not support automatic adjustment. As a result, data transmission fails when the NIC is changed to 100 Mb Full Mode and Mb Full Mode. Some high-end switches must be configured to automatically switch between full duplex and half duplex. Some switches do not support full duplex by default. There are two solutions: one is to adjust the switch settings to support full-duplex and half-duplex working states; another solution is to change the Link Speed/Dupler Mode of the NIC to Auto.

Fault resolution: we must make a choice for some network optimization articles. It is best to test whether the optimization project is feasible.

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