How to fix Error 324 Moodle EC2

Hi all,

I wanted to enable email based self-registration on my Moodle instance so followed the instructions here: http://docs.moodle.org/23/en/Email-based_self-registration but now I only get an error 324 (ERR_EMPTY_RESPONSE) from the server.

I saw somewhere (I can't find it again now) that I should check the settings in the php.ini file but I can't get to that either. I can't get this to work: http://answers.bitnami.org/questions/5/i-can-not-access-my-virtual-machine-using-ftp or this http://wiki.filezilla-project.org/Howto

So, the main question is how can I get back into the server? We'll deal tith ftp if and when that is needed...

Thanks in advance

David