I couldn't be bothered using Mixbus, I have 3 and 4, so I just fired up 4 to see, it starts fine and seems to work ok, I just run a test project I done ages ago, didn't do any tracking or editing or anything, just played the project. It wasn't the latest Mixbus 4 version as I got a popup telling me about a new version, 4.2 or something, but I couldn't be bothered. Windows is the latest version, I finally let it update, all seems well apart form re authing XLN's AD, AD2, AKeys and Mercurials U530 and Spark amp sims, other than that all seems fine.