• VSCode Version: 1.29.0-insider (user setup)
• OS Version: Windows 10 10.0.17134

more details - entire help entry
Version: 1.29.0-insider (user setup)
Commit: 931c220
Date: 2018-10-12T05:17:15.739Z
Electron: 2.0.11
Chrome: 61.0.3163.100
Node.js: 8.9.3
V8: 6.1.534.41
Architecture: x64

Steps to Reproduce:

1. open vscode with a git controlled folder.
2. from any branch select the scm icon in status bar to checkout a different branch and select origin/master in the command pallette popup while on say develop

Does this issue occur when all extensions are disabled?: Yes/No
Yes

this is the error I recieve

Here is the git log

> git checkout -q --track origin/master
fatal: A branch named 'master' already exists.
> git fetch
> git status -z -u
> git symbolic-ref --short HEAD
> git rev-parse develop
> git rev-parse --symbolic-full-name develop@{u}
> git rev-list --left-right develop...refs/remotes/origin/develop
> git for-each-ref --format %(refname) %(objectname) --sort -committerdate
> git remote --verbose

I normally do not use the insiders build but I installed it to test this out.

There may be a issue with my git for windows configuration and not vscode.
I recently updated my git for windows install and this problem started after the update.

If I simply execute git checkout master then the checkout works as expected it seems the problem only happens when using vscode scm features.