$ git push -u origin master To email@example.com:******/Demo.git ! [rejected] master -> master (non-fast-forward) error: failed to push some refs to 'firstname.lastname@example.org:******/Demo.git' hint: Updates were rejected because the tip of your current branch is behind hint: its remote counterpart. Merge the remote changes (e.g. 'git pull') hint: before pushing again. hint: See the 'Note about fast-forwards' in 'git push --help' for details.