default sessions tree missing all sessions gone

I am evaluating the Enterprise Edition. I have added two groups with about half dozen sessions in each group. All of a sudden the default Sessions tree is gone and is replaced with "Sessions- favorites only" and two empty group folders in the tree. The All Sessions tab is checked. I am using the default data source with the connections.xml file stored in my default user path.

I have noticed this error in the log: [6/16/2012 8:07 PM]ERROR System.IO.FileNotFoundException: Could not load file or assembly 'Microsoft.Web.Administration, Version=7.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The system cannot find the file specified.
File name: 'Microsoft.Web.Administration, Version=7.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35'

Don't know if my problem is related to the error or not. Everything was working fine until my last "Add new Session" attempt. I have a hard time believing all the sessions I created are actually gone.

My platform is W7 Pro 64bit. Most recent version of your software available via Trial Download.

Please advise.

Dave