Simple anti-customer solution-ADSL Problems

With the decrease in ADSL charges, more and more users are using ADSL as a broadband access method. The problems encountered during the installation and use of ADSL are also varied. I have encountered several examples. The fault is as follows:
Fault description 1: machine A is A Lenovo Zhaoyang laptop, originally A client in a lan. Currently, when A single-host ADSL Broadband Network is used as A terminal, it cannot be connected in any way, however, once you get it to an internet cafe and share it with ADSL as a client, you can access the Internet without any settings. This server is Win2000 + SyGate!
Fault Phenomenon 2: Both B and C computers are processing computers bought at a low price from a closed internet cafe. These computers are Internet cafe clients.
Fault symptom 3: The D host is a new fanwe and 2500 computer. Because the CMOS often loses power less than a month after it was bought, I switched one at the provincial capital office of Founder Company. In order to test whether the NIC of the host is normal, I tried a client in the company's LAN to share the Internet. However, when I got home and used as a terminal to access the Internet, I was unable to access the Internet on a single machine no matter how I debugged it.
Troubleshooting:

In order to locate the problem, we adopt exclusion, that is, we conduct in-depth and meticulous troubleshooting On A, B, C, and D from hardware to software and access lines, eliminate all doubts one by one to find out the crux of the problem.
First, we start by checking the NIC. First, we can confirm from the fact that they can share the Internet with the client that there is no problem with the NIC itself, and then we suspect that there is a problem with the NIC Driver, then, the original driver of the NIC is uninstalled and the driver is re-installed. The fault persists. Is there a fault in the ADSL line? In line with this idea, we have switched a broadband access line for the above machines through the Telecommunications Bureau, then the ADSL Modem, and finally brought the above machines to our Organization, I found a connection line for a Single-host machine that can access the Internet normally, but still cannot access the Internet on the single-host machine. In this way, the failure in connection with the ADSL Modem is ruled out. Finally, there is no way to fix this problem after formatting machine B and machine C and re-installing the operating system WinMe). After the problem is solved, it is tested to install Win98.

At this time, although the problem was initially solved, it was not easy for us. Why do I have to format a computer that has used a client in the LAN and reinstall the system before accessing the Internet as a host? Isn't there a simpler method? We have been thinking and discussing such a problem for several days. During the discussion, I suddenly thought about whether the NIC has any information residing on the machine, which makes the machine unable to act as a host for ADSL? Yes, it must be.
So we started to look at the registry until we remembered the "winipcfg" command that was previously used to query the IP address of the local machine. I wonder if it will be useful this time? Therefore, the author runs the "winipcfg" command in "run" in the "Start" menu, and an information box pops up. The current adapter (Network Card) information, adapter address, IP address, subnet mask, and default gateway are displayed. But what attracts me most is the "release all" and "update all" buttons at the bottom. At this point, I carefully clicked the "release all" button in order, and then clicked the "update all" button.
When I started the IE browser again, the miracle appeared, and the long-time homepage screen was quickly displayed in front of me!