Github error bad signature

Describes the cause and action for error messages.

Error Message(English)：
error bad signature

Resolution

.git/indexが壊れたときの対処法(の続き) - mikan_daisuki's blog
http://mikan-daisuki.hatenablog.com/entry/2015/08/01/110752

「'git status'がコード128で終了しました」というエラーが出たときの対処方法 ...
http://executing.hatenablog.com/entry/2014/06/11/234730

Git 出?error: bad signature fatal: index file corrupt的解决方法 - GitHub
https://github.com/wenhelinlu/spark/wiki/Git-%E5%87%BA%E7%8E%B0--error:-bad-signature-fatal:-index-f・・・

gitリポジトリのindexが壊れたときの復旧法 | Modnaromem - Index of
http://harmonies.sakura.ne.jp/harmonies.sakura.ne.jp/2017/12/20/git%E3%83%AA%E3%83%9D%E3%82%B8%E3%83・・・

Is there any solution for git - error: bad signature without ...
https://stackoverflow.com/questions/46687977/is-there-any-solution-for-git-error-bad-signature-witho・・・

Error while checkout git branch
https://stackoverflow.com/questions/45364703/error-while-checkout-git-branch

Restore broken branch/resolve detached HEAD state?
https://stackoverflow.com/questions/43747298/restore-broken-branch-resolve-detached-head-state

Suddenly every git command causes `error: bad signature` in ...
https://stackoverflow.com/questions/35061062/suddenly-every-git-command-causes-error-bad-signature-i・・・

Unstaged changes left after abrupt shut down
https://stackoverflow.com/questions/31793581/unstaged-changes-left-after-abrupt-shut-down