session_proxy problem

[spuntotheratboy]

Hello,

I'm trying to install on a Macbook running OS 10.10.3, Apache/2.4.10 (Unix), PHP 5.5.20, 5.6.21 MySQL Community Server.

I had to edit the database details in sites/default/settings.php by hand in order to get past a message about Drupal already being installed. Now it looks like it's going to install but as soon as I get to http://localhost/~Guest/install.php?profile=cambridge&locale=en I get this error:

Fatal error: Cannot redeclare drupal_session_initialize() (previously declared in /Users/Guest/Sites/includes/session.inc:240) in /Users/Guest/Sites/sites/default/modules/session_proxy/session.inc on line 48

I don't know enough to sort it out - can I disable the session_proxy module? Should I? The reason I'm installing is so I can familiarise myself with Drupal, as much as with the Cambridge system: that is to say, this installation isn't production so I suspect the session handling isn't really very important, as long as it doesn't cause the installation to fail!

Any advice?

Thanks,
Ben