This is just a standard SQL connection error. The user who you are attempting to use cannot login or access the SQL Server connection for some reason. If you'll notice, it is trying to connect to SQL Server and I do not see that you have specified a SQL connection.
Are you reusing this application key: StratFarmeSmaApp?
If so, then this could be your problem. Change this key by adding a "1" to the end or something and it should force the connection wizard to come back up. Make sure that you are pointing to the VFP database and see if the error persists.
ConnectionManager.ApplicationKey = "StratFarmeSmaApp1"; If this doesn't work, remove the ConnectionManager.SetConnections() in the SetDataSOurces and hard code your connection and see if the error persists.
MicroFour.StrataFrame.Data.DataBasics.DataSOurces.Add(New VFPDataSourceItem("","provider=VFPOLEDB;data source=C:\\MyDatabase.dbc"));
In fact, the first thing you may want to do is turn on database debugging so you can see exactly what is happening. After the ConnectionManager.SetConnections() method, add this code:
MicroFour.StrataFrame.Data.DataBasics.DataSources[0].SetDebugOn(@"c:\Output.html",true);
Run the application again and it will log every piece of the data interaction. One the error occurs, bring up the HTML file and you will be able to see the connection and exactly what happened.