The SDK folder was empty for C:\Users\userID\AppData\Local\Android\SDK
For displaying hidden AppData or Local subfolder: Tools, Folder Options, View, Advanced Settings, Files and Folders, select option Show hidden files, folders, and drives.
The SDK folder should contain the following subfolders:
- build-tools.
- emulator.
- extras.
- patcher.
- platforms.
- platform-tools.
- sources.
- tools.
Downloaded the zip file to create the tools subfolder
from link, sdk-tools-windows-4333796.zip
of section, Command line tools only, Platform Windows
within URL, https://developer.android.com/studio
Zip file name: sdk-tools-windows-4333796.zip
Copied this zip file into C:\Users\userID\AppData\Local\Android\SDK
Unzipped this file, which created tools subfolder.
Downloaded zip file to create the platform-tools subfolder
from link, Download SDK Platform-Tools for Windows,
within URL, https://developer.android.com/studio/releases/platform-tools.html
Zip file name: platform-tools_r28.0.2-windows.zip
Copied this zip file into C:\Users\userID\AppData\Local\Android\SDK
Unzipped this file, which created platform-tools subfolder.
Open Android Studio and follow prompts. Other subfolders will be created automatically.