Fixed it! It turned out to be a server configuration problem.
For the benefit of anyone else having the same issue on a Windows local machine running Apache, in your apache instillation find the file “httpd.conf” (in the conf directory) open it in your text editor of choice (Notepad etc) find the first two instances of the line “AllowOverride None” which appears to be the default when you install Apache and change to “AllowOverride All”. Restart your machine for the new setting to take effect and bingo, problem solved.