git untrack

C++
Commit any files that you need to change/delete to the repo. Then:

git rm -r --cached .  # this will clean all files from cache. To clean a single file, exchange '.' with filename
git add .  # add all of the now uncached files that are not gitignored to the staging area
git commit -m "fix .gitignore"  # commit the changesgit 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 filenamegit rm -r --cached .git rm -r --cached <file>

Source

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