SharePoint - Claims Based Authentication : Access Denied

I have a web application extended to use FBA now FBA and Windows Authentication site give me Error Access Denied when I try and log in. I get this error as well : An exception occurred when trying to issue security token: The security token username and password could not be validated..In Windows Event viewer

I upgraded from MOSS 2007 to 2010 using an in-place upgrade and the site worked fine until I changed it to Claims Auth so that I could set up my FBA....please assist

Hi,

There are not a lot of differences with configuring FBA for SharePoint 2010 compared to 2007, but there are a few.  For instance, SharePoint 2010 no longer supports “classic FBA”, rather forms based authentication is provided through Claims Authentication.
To implement FBA in 2010 follow this article http://donalconlon.wordpress.com/2010/02/23/configuring-forms-base-authentication-for-sharepoint-2010-using-iis7/

Thanks, I had managed to set it up, but the only thing is I am getting access denied when I try and enter the site.