I've been stuck all day on this issue, looking for an answer here :( ...
I'm working alone on a project and I used github until now to save my work other than on my computer.
Unfortunately, I added a very large file to the local repository : 300mb (which exceed Github's limit).
What I did
I will try to make an history of what I made :
git add *
git commit -m "Blablabla"
git push origin master
When you deleted your file, that will be a change and that is the unstaged change that git is complaining about. If you do a git status you should see the file listed as removed/deleted. To undo this change you should
git checkout -- <filename>. Then the file will be back and your branch should be clean. You can also
git reset --hard this will bring your repo back to the status where you made your commit.
I am assuming that it is the last commit that has the very large file that you want to remove. You can do a
git reset HEAD~ Then you can redo the commit (not adding the large file). Then you should be able to
git push without a problem.
Since the file is not in the last commit then you can do the final steps without a problem. You just need to get your changes either committed or removed.