How to change the default shell in Cygwin

If you are able to login using your regular user, just change the root users shell directly:

sudo gedit /etc/passwd

Find the line for you root user, usually the first one, and change the last part from

...:bash

to

...:/bin/bash

And you should be good to go.

(NB: Replace gedit with whatever editor you fancy.)

Try using the chsh command.

e.g.

chsh -s /bin/zsh

You can confirm the location of zsh by running whereis zsh, or alternatively simply run

chsh -s $(which zsh)

If you want to change the shell for a user account other than the one you're logged into, you'll need to run it as root, so to change john's shell, do:

sudo chsh -s $(which zsh) john

Note that you'll need to log out and log back in for the change to go into effect. If you're using Gnome or some other window manager, you'll need to completely log out of that session as well—simply closing and opening your terminal is insufficient.