"so why removal of WOW16 and NTVDM? Dosbox works."
Once again: AMD removed the Virtual86 mode from CPU in 64 bit mode. Without that CPU mode, WOW16 and NTVDM can't work.
DosBox is a software CPU emulator, while the Virtual86 mode allows for running real mode software directly on the CPU, once the CPU is in protected mode automatically trapping operations forbidden in protected mode and allowing the OS to perform them as required.
If older VB applications use 16 bit libraries or installers, they won't work on 64 bit Windows exactly for that reason.
With virtual machine easily available, it takes little to run DOS in one if you need to run 16 bit code.
Biting the hand that feeds IT
