Data Connections > Add SQL Server Compact Compact 4.0 Connection... > Test Connection
Toolbox v4.1.0.0 / VS Community 2013 / Win7 Pro 64-bit
On attempting to Test Connection the Toolbox said the db file is from an earlier version, would you like to upgrade it? The upgrade failed with the error messages shown in the attached screenshot. This happened repeatedly for this small v3.5 db.
Upgrade was successful using
```
SqlCeEngine engine = new SqlCeEngine(ConnectionString);
engine.Upgrade();
```
It just worked instantly and silently. After this the Toolbox was able to open the new db file (Test Connection succeeded) as a v4.0 db.
JPL
Toolbox v4.1.0.0 / VS Community 2013 / Win7 Pro 64-bit
On attempting to Test Connection the Toolbox said the db file is from an earlier version, would you like to upgrade it? The upgrade failed with the error messages shown in the attached screenshot. This happened repeatedly for this small v3.5 db.
Upgrade was successful using
```
SqlCeEngine engine = new SqlCeEngine(ConnectionString);
engine.Upgrade();
```
It just worked instantly and silently. After this the Toolbox was able to open the new db file (Test Connection succeeded) as a v4.0 db.
JPL