When you install a new version of ArcGIS for Desktop, ArcGIS Engine, or ArcGIS for Server Workgroup edition, you can upgrade the geodatabases you have stored in your SQL Server Express instance (the database server).
You also might need to upgrade the SQL Server Express instance to a newer, supported SQL Server Express release.
As newer releases of SQL Server Express are supported, these installations are shipped with ArcGIS for Desktop, ArcGIS Engine, and ArcGIS for Server Workgroup edition. You can use these newer installations to upgrade your SQL Server Express instance.
Before upgrading the SQL Server Express instance or any geodatabases, create backup files of all geodatabases.
See Upgrade SQL Server Express and Upgrade a desktop or workgroup geodatabase for instructions.