Solution for keyboard failure after computer startup

When I turned on the computer and found the password, the keyboard didn't work. I tried the keyboard and it didn't matter. The socket was fine. I could enter the safe mode. It was very strange. Yesterday, I can't use it today. I haven't found it for a long time. I came out, and later used the PE disk to erase the password, and finally entered the system. In the device management, I found that the keyboard driver has a yellow exclamation mark. It is preliminarily judged that the driver fails to load and reinstall. Later I thought that I might have caused the software to be uninstalled yesterday. I found a solution and finally solved it. In this summary, I will encounter similar problems in the future. 1. Open the registry regedit and navigate to HKEY_LOCAL_MACHINESYSTEMCurrentControlSetControlClass{4D36E96B-E325-11CE-BFC1-08002BE10318} 2. Delete the UpperFilters item, uninstall the device, and restart. 3. Then locate HKEY_LOCAL_MACHINESYSTEMCurrentControlSetControlClass{4D36E96B-E325-11CE-BFC1-08002BE10318} 4. Add the string UpperFilters, the content is kbdclass, uninstall the device, restart. The problem is solved! It may be caused by the installation of some software, the driver of the PS/2 interface has been tampered with, the information in the registry has been modified, so the keyboard itself is OK, but it is not connected to the computer, the middle driver there is a problem. Put the problem and solution for this keyboard not working properly so that friends who encounter the same problem can query. Serious warnings to some undocumented programmers, the software must be clean, do not uninstall a disaster, Nima, almost redo the system. This article comes from [system home] www.xp85.com