After you install Notepad++
1. Navigate to: Settings > Preferences
2. On the left go down to Language, then go across to Tab Settings and scroll down to yaml then click on it.
Make sure Use default value is unchecked. Set Tab size to 2 and check Replace by space
Then click close and Notepad++ will use spaces instead of tab.
One of the most common problems with config files is spaces or tabs where they do not belong, here are 2 ways to fix this
1. Open the file in Notepad++ select Edit > Blank Operations > TAB to space, then select Edit > Blank Operations > Trim Trailing Space
2. Copy the contents of your file and then past it into a YAML Parser if there are any errors, this will tell you what line your errors are on