HELP! Membership site not accessible!

My membership site, has been running fairly well since January. Today I was trying to improve my SEO and installed Wordpress SEO and Redirection (to help with the changed permalinks).

After installing and configuring these plug ins I started getting e-mails from my members saying they could not access the membership pages.They were redirected to the 'members only' page.

I backed out of the redirection plug in by deleting all of the settings and deactivating the plug in. I did the same with the Wordpress SEO.

There is still a problem with the members signing in. When they sign in they get a 'members only' page.

I have checked my membership levels, reset them, looked at the options page, verified my membership tables and still cannot reach any of the membership pages when I test the sign in as a member.

PLUS, I just updated to wordpress 3.2 and now when I try to access my site through the dashboard or via the home link I get this error message:

Fatal error: Call to undefined method WP_User::WP_User() in /home/sisterh0/public_html/wp-content/plugins/membership/membershipincludes/classes/class.membership.php on line 23

I'm looking for a bridge to jump from! Please help.