Just set up my first Pi for the first time using a Windows computer - I don't have another Linux system available to me. I got the Pi working by flashing the Raspian disk image onto the SD, and this booted fine.
I have an Adafruit screen which I installed using the instructions on this page and VNC. (Not sure that this is relevant - just including it for completeness' sake.) When that installation prompted me to reboot, I did so, and now the Pi doesn't progress past "rc-local.service" when booting and doesn't reach the desktop.
I was able to edit a cmdline.txt in the SD card on Windows and open a shell immediately on boot before logging in as per this thread. From there I was able to
vi /etc/rc.local and see that the screen installation had indeed changed the file (but not by me). I was not able to edit it as the system was in read-only mode.
Given that I only have a Windows system to work with, how can I remedy this? If that solution is just to start from scratch, how can I prevent it from happening?