Git doesn't change working directory

I’m using Windows 10. Before I install git 2.6.1.windows.1, I have installed git 1.9.5.github.0 (by installing GitHub Desktop), it works just fine.
But when I installed git 2.6.1.windows.1 (from git-scm.com), I’m not able to use git anymore:

After that, I returned to the old version of git – git 1.9.5.github.0, but the fault still there.

I think git didn’t change its working directory, I have no idea.
Now, I’m not able to work with git.

How to fix this?

EDIT 1:

Again, this is not the first time I use git, I never forget cd myproject. However, although I moved to the project, git “thought” itself working in C:\Program Files\Git and doesn’t “realize” that the working directory has been changed! That’s the problem, As the title: Git doesn’t change working directory

EDIT 2:

When Get-Command git in powershell, it returns:

CommandType      Name         Version      Source
-----------      ----         -------      ------
Application      git.exe      2.6.0.0      C:\Program Files\Git\cmd\git.exe

EDIT 3:

@EdwardThomson asked me for output of git config --list and Get-ChildItem Env:

  • Output of git config --list: http://pastebin.com/qUxKnBiT

  • Output of Get-ChildItem Env: http://pastebin.com/ShPcypF0

SOLVED:

I have received an email which mentions GIT_DIR, then I know what exactly caused my problem! It’s because of environment variable GIT_DIR, I set GIT_DIR to the folder which contains git for convenience without aware that git uses it

Thank you for trying to help me.

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