The database schema version (2800) is higher then the running Sitefinity version (1733). Downgrade is not allowed.
Sadly I haven't messed with the OpenAccess yet so I couldn't even guess at to what it might be.
Cannot open user default database. Login failed.
Login failed for user 'NT AUTHORITY\NETWORK SERVICE'.
Could not load file or assembly 'Telerik.OpenAccess, Version=2011.2.713.3, Culture=neutral, PublicKeyToken=7ce17eeaf1d59342' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
I ended up doing two things which got me by this error. 1- make a backup of your project.