[Plugin WP E-Commerce] Activation breaks backend?

Hey. I’m relatively new to the WordPress software. I’ve been trying to set up an e-commerce site. I installed WP on my server, updated it to the newest version, all that jazz.

I installed WP E-Commerce alongside some other plugins originally, and when I activated it, I was no longer able to access the backend, I got an HTTP 500 error.

Hm, okay, so I remove WordPress, reinstall, update, and add WP E-Commerce to a vanilla setup. Same thing. When I click “Activate” I am immediately greeted by a 500 error page, and attempting to return to the dashboard, or to the wp-admin page, gives me the same error. I’m thinking it has to be some conflict the plugin is causing but I don’t know what it could be.