I've been using sourcetree for some years and so far it's just worked with no problems. However last week it started coming up with this error:

As you can see it just goes on and on and on.
I've googled and the only solution I've found is to set autocrlf to true.
This doesn't work for me though.
It's quite a problem as I can't really do anything in sourcetree at the moment, despite not having committed for over a week it says "nothing to commit", and then pops up a few more errors every time I alt+tab back to sourcetree.
Does anyone have a solution for this? 
I've tried both re-installing sourcetree and rebooting my computer to no avail.