git untrack file

git rm --cached <file>

git rm -r --cached <folder>

Update your . gitignore file – for instance, add a folder you don't want to track to . gitignore .
git rm -r --cached . – Remove all tracked files, including wanted and unwanted. Your code will be safe as long as you have saved locally.
git add . – All files will be added back in, except those in . gitignore .

git rm --cached filename

git rm -r --cached .

git ls-files --ignored --exclude-standard -z | xargs -0 git rm --cached
git commit -am "Remove ignored files"


// answer from: thSoft