How do I configure ConEmu to run Cygwin Bash?

This might helps others.

It looks like version 140310 of ConEmu automatically detects CygWin Bash.

If you've installed Cygwin after you installed ConEmu, you'll need to Reload... your list of Tasks.

1. Go to Settings... (Win + Alt + P)
2. Navigate to your list of Tasks (Startup > Tasks)
3. Click on the Reload... button.

You should now see {CygWin bash} as one of your options in the list of predefined tasks:

PS -- If this method doesn't work, try resetting your ConEmu settings (click the Reset... button at the bottom of your Settings window).

or instead of

C:\cygwin\bin\bash.exe

use

C:\cygwin\Cygwin.bat

Ensure that Bash is receiving a sensible value for $PATH; usually it inherits that from whatever calls it, but ConEmu is a Windows application, so all it's going to provide is whatever you have set for %Path%. Generally that doesn't include the Cygwin path directories, so Bash doesn't know where to look for ls, &c.

The way I'd solve this would be to, via whatever means ConEmu offers for doing so, pass --login -i as command line arguments to Bash; this will tell it you're running it as an interactive login shell, so it will read /etc/profile, ~/.profile, and ~/.bashrc on start. In my experience, that's been enough to give it a sensible $PATH; if that doesn't work for you, you could specify it explicitly with a line like PATH=/bin:/usr/bin:/usr/local/bin:[...]:$PATH in your ~/.bashrc.