I keep getting this error when I try to create a version to edit data. I never had this error before creating a version in 10.1, but recently my computer crashed. We installed 10.2 on my computer once we got it back working. I tried googling for the specifics of this error, but can't find out what is causing it. If anyone has any knowledge on this error please let me know what I can do to fix it.
Did you enable the geodatabase functionality on the SQL Server Express instance? (I am assuming that this is a geodatabase).
The native client is a separate install that can be downloaded form the MyEsri site. I would think that it was installed if the SQL Express and ArcGIS Desktop client are on the same machine.
You may want to open an Esri Technical Support case if you need more help.
What is the version of the underlying Database that you are connecting to?
SQL Server 2000\2005....?
You mentioned that you had installed SQL Server 2012 Express in one of the posts....but still just wanted to confirm this.