Invalid connection error on SQL Server 2008
I found a similar question with an answer, this one https://superuser.com/questions/314206/cannot-connect-to-sql-server-from-excel-2007 on superuser. It turned out that for some reason, on the MS SQL Server 2008 I had to put a named instance and not just the name of the server, e.g. if the server name is "yoda", on the application configuration I have just to put "yoda" if the backend is a MS SQL Server 2005, if I use MS SQL Server 2008 I have to put "yoda\sqlexpress,1433". I do not know if an alternative solution could be updating some libraries.