Android SDK Setup (API Level 19 and 21) The following package(s) were not downloaded: addon-google_apis_x86-google-19. Please check your internet connection and try again.
how can fixed it
Ensure that your firewall / proxy isn't blocking the traffic. You'll need access to dl.google.com. I've also seen some anti-virus applications interfere with the SDK so it might be worth temporarily disabling your antivirus to see if this is the problem.
If you're still having problems it could be down to a permissions issue - if you're in Windows try running Visual Studio / Android SDK Manager as Administrator.
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