问题：运行SDK Manager.exe老是提示这样的错误：
Fetching
https://dl-ssl.google.com/android/repository/addons_list-1.xml
Failed to fetch URL
https://dl-ssl.google.com/android/repository/addons_list-1.xml, reason:
Connection to https://dl-ssl.google.com refused
Fetched Add-ons List successfully
Refresh Sources
Fetching URL:
https://dl-ssl.google.com/android/repository/repository-6.xml
Failed to fetch URL
https://dl-ssl.google.com/android/repository/repository-6.xml, reason:
Connection to https://dl-ssl.google.com refused
解决方法：
在C:\Windows\System32\drivers\etc\
找到hosts，用记事本打开hosts文件，最后一行加74.125.237.1 dl-ssl.google.com