为什么我的电脑重装系统之后就不能上网了?

你在文件夹选项里把隐藏打开，打开你的D E F...在根目录下会看到4个隐藏文件，把这几个都删了，还有在C:/windows/下面还有几个一样的文件，也都删了，重启=OK
如果不能看到隐藏文件 进不了注册表就把下面的保存为A.KEY 运行就可以
Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Advanced\Folder\Hidden]
"Text"="@shell32.dll,-30499"
"Type"="group"
"Bitmap"=hex(2):25,00,53,00,79,00,73,00,74,00,65,00,6d,00,52,00,6f,00,6f,00,74,\
00,25,00,5c,00,73,00,79,00,73,00,74,00,65,00,6d,00,33,00,32,00,5c,00,53,00,\
48,00,45,00,4c,00,4c,00,33,00,32,00,2e,00,64,00,6c,00,6c,00,2c,00,34,00,00,\
00
"HelpID"="shell.hlp#51131"

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Advanced\Folder\Hidden\NOHIDDEN]
"RegPath"="Software\\Microsoft\\Windows\\CurrentVersion