可能是hosts损坏了，修复一下。

手动修改方法如下：

1.C:\Windows\System32\drivers\etc\

在hosts文件上点右键-属性去掉只读

2.双击 hosts 选择记事本打开，删掉里面全部内容后，文件-保存退出即可

你先试一下这个，如果不行，我发完整HOSTS里面的内容给你。

如果还不行，将HOSTS里面的内容替换成以下的：

# Copyright (c) 1993-1999 Microsoft Corp.

#

# This is a sample HOSTS file used by Microsoft TCP/IP for Windows.

#

# This file contains the mappings of IP addresses to host names. Each

# entry should be kept on an individual line. The IP address should

# be placed in the first column followed by the corresponding host name.

# The IP address and the host name should be separated by at least one

# space.

#

# Additionally, comments (such as these) may be inserted on individual

# lines or following the machine name denoted by a *#* symbol.

#

# For example:

#

# 102.54.94.97 rhino.acme.com # source server

# 38.25.63.10 x.acme.com # x client host

127.0.0.1 localhost