1、首先找到host文件：C:\Windows\System32\drivers\etc

2、打开host文件：

# Copyright (c) 1993-2009 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

# localhost name resolution is handled within DNS itself.
# 127.0.0.1       localhost
# ::1             localhost
0.0.0.0 account.jetbrains.com

3、找到38.25.63.10 x.acme.com ，注意#为注释，在下方添加新的

# Copyright (c) 1993-2009 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       '
127.0.0.1 a.cn       
# x client host

# localhost name resolution is handled within DNS itself.
# 127.0.0.1       localhost
# ::1             localhost
0.0.0.0 account.jetbrains.com

4、进行cmd，ping发现指向127.0.0.1