Unable to access Android SDK add-on list

There may be a few reasons why you are unable to access the Android SDK add-on list. Here are some potential solutions:

1. Check your internet connection: Make sure your computer is connected to the internet and that there are no connectivity issues.

2. Update SDK Manager: Open Android Studio and go to SDK Manager. Check for updates and install them.

3. Clear cache: Clear the cache in Android Studio by going to File > Invalidate Caches / Restart.

4. Disable proxy settings: If you are using a proxy server, try disabling it and then accessing the add-on list.

5. Check firewall settings: Make sure that your firewall settings are not blocking access to the add-on list.

If none of these solutions work, you may need to reinstall Android Studio.