Directory: Unable to configure settings in multisite set up

Hi, I activated the plugin for one of my blogs. I enabled it for this particular "blog" only, and when I activated it and went to the first step which is to "configure your settings", I get this error: You do not have sufficient permissions to access this page. I don't know why... Please help!

In this site, I have no other plugins active and I'm using the standard 2011 plugin.


P.S. I have tried switching themes and this didn't help either. This is a support question thanks!