Processes sometimes don't appear to execute, on windows

I'm trying to execute git commands:

git init
git add
git commit
git status --porcelain

I've tried using variations of:

def p = "cmd /c dir".execute()

and waitForProcessOutput

and even using ProcessBuilder directly.

On my laptop it all works. On windows server, the commands sometimes 
don't appear to execute.

Any ideas?

Kendall