jeffreydriver
After searching around for some time, I haven't managed to find a solution to this issue.
I attempted to install a new plugin (Google Analytics), but it failed and I got the message "Security Token did not match. Possible CSRF attack."
Since then, whenever I try and save any changes, whether it's adding or changing a page, changing configuration settings, installing/uninstalling plugins etc. I've read the page regarding CSRF, but it hasn't helped me narrow down what's causing the issue, or how to properly resolve it.
Thanks.