I am a 68-years old Neurosurgeon - a die-hard-fan-*censored*-avid-user(for over three decades) of MS DOS 6.22 with QBasic1.0, Foxpro for DOS 2.5 a and Wordstar 4.0 for all my work - taking at the end of every day a zipped back up of all transaction files
of the day into a
single 1.44 MB FDD and back them upto my other PCs via FDD / USB Pen drive / Network etc., I use Windows only for surfing - telemedicine etc.,
Recently my 10 year old mobo started acting funny - weird messages about FDD, Keyboard not present etc., After sending the old mobo to service, I shifted the MS DOS ec., Hard disk to another mobo - removing a pre-existing XP Hard disk leaving the old MS
DOS as the only HDD.
MS DOS booted fine from the old HDD and did all internal commands like dir, type, copy etc but hung up on all .exe files - scandisk,
qbasic, fox, foxpro, ws etc.,
I then booted from a DOS Boot Floppy and now all .exe files worked fine, except the inevitable time-lag of the processor looking up
command.com in the slower FDD each time I gave a command fom the command line or via MS DOS Batch files.
I then used sys.com in the FDD to transfer the system to the C:\ drive. Now command.com in the FDD and the C:\ on the HDD had the same size
and date stamp. Yet when I rebooted fom the hard drive - cold and hot, the .exe files did not work and the system hung!