I have MATLAB 2016a and 2018b installed on the same machine. We don't want to uninstall 2016 yet because we have significant amounts of code written for 2016a which might not work on 2018b. The problem is, everything defaults to opening with 2016a. I have tried to fix this though going into the Windows options of changing what programme opens files, but the problem is that when I browse to the 2018b executeable it just notes that it is also MATLAB and leaves it as 2016a. So this is probably more a bug in Windows than strictly a MATLAB issue. But does anyone know how to fix it? I know of workarounds like opening 2018a first then doing file > open, but we want it to work properly.