Date: Sat, 04 Apr 2015 21:38:21 +0300
From: Eli Zaretskii <eliz@gnu.org>
Cc: 20237@debbugs.gnu.org
I think you need to use this instead:
(setq python-shell-interpreter "/cygdrive/C/Python27/Scripts/ipython")
Or something like that -- I don't use Cygwin, so I might be mistaken
about the exact format you need to use.
Actually, if you use this format, you'd probably also need to use
cygwin-mount as well.
So the second alternative, to remove the setup for Cygwin Bash, is IMO
better. Mixing a native Windows Emacs with Cygwin is a tricky
business.
Yet another possibility is to use a Cygwin build of Emacs.