Recently I’ve experienced a weird behavior in a Cygwin installation on Windows 7. When pressing the backspace key Cygwin falsly interpreted it as a space.
Luckily, the problem is rather easy to fix. The easiest way (which did not work everytime while testing) is to simply reinstall terminfo and termcap via setup.exe, as mentioned here: Backspace does not work in Cygwin. If you don’t have termcap installed install it but make sure to reinstall terminfo properly too. At best this is all you need to do to get your backspace back again.
If not, you might need to remove .bashrc from your home folder, e.g. /cygwin/home/you/.bashrc. Then, just to make sure reinstall terminfo and termcap again. This always worked for me.
Enjoy your backspace 🙂