I still do not understand. I ran and worked with MS-DOS in production use for years. I am that old. I have deployed hundreds of DOS machines and I was an exper

I still do not understand. I ran and worked with MS-DOS in production use for years. I am that old. I have deployed hundreds of DOS machines and I was an expert in DOS memory management. I installed lots of apps from floppies as well. No, usually installation floppies were _not_ bootable, in my extensive experience. If they were, I can't see how or why that would affect the app so long as the app wasn't tied to one specific version of DOS. At the time when DOS ruled business PC computing, there were not very many alternative versions. Even DR-DOS came along quite late. Aside from DR's own multitasking TASKMGR.EXE I don't think I ever saw anything else that was specific to DR-DOS. GEM and ViewMax ran fine on MS-DOS. There was no practical difference between IBM's PC DOS and MS-DOS except for BASICA. Only when MS dicontinued MS-DOS did IBM PC DOS start to diverge, dropping BASIC for Rexx, dropping EDIT.EXE for IBM E, and so on. I cannot work out what you could mean. Perhaps specific examples would help.