android-sdk-windows无法正常更新

在www.android.com下载最新版的android-sdk_r20.0.3-windows之后，点击SDK Manager.exe，发现无法显示Updates/New的内容，因此无法进行更新。

菜单Tools-->options中的Force https://...sources to be fetched using http://...勾选上之后，问题依旧。
最终解决方案：

在C:\WINDOWS\system32\drivers\etc目录下，找到hosts文件，在文件末尾加上

74.125.237.1 dl-ssl.google.com

如下：

# 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
74.125.237.1 dl-ssl.google.com

问题得到解决。

在windows7下，使用管理员身份运行记事本，打开hosts文件，修改后就可以直接保存了。