VS6 ? and VS11 are basically 2 different animals. Code written in 6 ? will have to be reworked for 11 or 13 or 15 or Community which I am running now. The coding models and commands have changed greatly over the years, as has so much more. I had to revamp code 2 times for a Fire Flow (water needed) calculations program I wrote that started in QuickBasic and I ported to VS 95 in VB. It's no longer being reworked but I do have some other items I have been playing around with...
Yes I know how my PC runs "under the hood"....
The installer is getting a out of range response from the OS query and going to the unknown OS error out.
VS Community is free. The EULA lays out what you can do with it which is a bit relaxed from Express. If It's gonna be commercial you will still need pro or better, The EULA is different.