One 、 cause

​ at present Java The learning of has reached the stage of advanced framework , The documents given by the teacher are all big , So I started to unload some unused software , Delete some unused files , Clean up the registry … such as Vm vare and oracle vm, These two have hardly been used , Even if you need follow-up teachers will also give , Restart after unloading , broken , The keyboard doesn't work well , Fortunately, the mouse can be used , also win10 The built-in flat panel mode solves the problem

Two 、 Cause analysis

​ When uninstalling, I cleaned the registry , I found a problem with the string value in the registry of the keyboard , That's the following ：

Computer \HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class{4d36e96b-e325-11ce-bfc1-08002be10318}\UpperFilters

​ I found that the numeric data in this string is kbdclass and vmkbd3, I think this is the problem vmkbd3 On ; In reason , The numerical data in this file is only kbdclass Just go , Unexpectedly, there are more vmkbd3, Just look at the name and you'll know Vm of

3、 ... and 、 Problem solving

According to the above reason analysis , Start the following solving steps ：

1. take UpperFilters Delete , Then in the device manager, set the yellow exclamation point under the keyboard HID Keyboard Device Drive all unloaded , Others are also uninstalled
2. Restart the device after confirming that the uninstallation is successful
3. Or go back to the registry , Go back to that position , Right click the blank space to create a new string value , The value name is ：UpperFilters; Data data is ：kbdclass
4. Then unload the driver
5. Restart the device after confirming that the uninstallation is successful

Perfect solution