Thanks a lot Tim, but it doesn´t work.

I knew the issue of the Data Source space in the connection string, that is incorrect in the dev guide. Using the DataLayerGenerator the connection string should finish with a semicolon. I have test it with AutoEndEdit=true too. I have used your string too, but nothing works. I can still get all the data but cannot save. The last string I used was the string provided in the Server Explorer, it is a little different from yours:

value="Data Source=C:\VSProjs\Prueba\PruebaVDB\PruebaVDB.vdb3;Open Mode=NonexclusiveReadWrite;Password=;"

I´m using the last 3.5 build 84 release. I have recompiled the MM .NET VistaDB adapter and the datalayergenerator as in the dev guide. The original release of the MM .NET was provided with the 3.5 build 42 release. I don´t think that it should be the problem.

I´m creating a WPF app. It is almost finished using SQL Server (I hope next week), but my customers need VistaDB so this problem is driving me mad.

I will try with some other combinations and check the mmDataAccessVistaDB class to find the error source.

some other help will be appreciatted.

Best Regards,
Antonio