I was upgrading a site (I thought) from SharePoint 2007 to SharePoint 2010 Beta 2 using the attach Content Database method. When I tred to access the site I got the following error message :-

Server error: http://go.microsoft.com/fwlink?LinkID=96177

If you followed this link to went to this page :-

Upon further investigation of the upgrade log I found the following error message :-

[OWSTIMER] [SPContentDatabaseSequence] [ERROR] [11/23/2009 5:38:07 PM]: Cannot upgrade an object [SPContentDatabase Name=WSS_Content_edit_internet_nigel] whose build version [14.0.4006.1030] is older than the [14.0.4514.1000] minimal supported beta version [Microsoft.SharePoint.Upgrade.SPContentDatabaseSequence].

What really meant was I could not upgrade from a Beta 1 site to a Beta 2 site !