Update the c: \ windows \ system32 \ drivers \ etc \ host file.
Step 1
Open tools> options under SDK manager and select force https ://... Sources to be fetched using http ://...", Use http.
Step 2
Go to c: \ windows \ system32 \ drivers \ etc \, right-click and select notepad to open the hosts file. Copy the following text in it. The content is as follows:
(Special emphasis: paste the following content after the original content, rather than overwrite it ):
# Google Homepage
203.208.46.146 www.google.com
# This line is used to enable the official Android development website. Now it seems that you can enable it without using VPN.
74.125.113.121 2.16.android.com
# Download the updated content from the following address:
203.208.46.146 dl.google.com
203.208.46.146 dl-ssl.google.com
Step 3
In sdkmanager, select the project to be updated and directly update the project. It is OK if the network is updated;
SDK update Solution