I had the same "Stream Finished" error when I upgraded from 10.3.1 to 10.6 and tried to connect to our old SQL2005 servers. I uninstalled 10.6 and found that I could connect to the database with 10.4.1 and 10.4 installed, but although I could view data, some processes (e.g. Table to Table with a Where statement) would still fail. I rolled back again to 10.3.1 and everything is working again. As George said, I suspect this is more luck than anything else and I wonder if there is other functionality that is not working that I have not noticed (yet). For now though, I'm going to have to stick with 10.3.1 until we can get our 2005 SQL servers upgraded.