From everything I've read, 64-bit Windows will not run 16-bit applications, because the 64 bit version of Windows does not include NTVDM (NT Virtual DOS Machine) or any support for a 16 bit subsystem. You can set up NTVDM to run in a 32-bit version using a virtual machine, or something like DOSBOX or vDOS, or enabling and installing NTVDM on a 32-bit version of Windows.

Perhaps your initial upgrade to Win7 was 32-bit?

I have generally used XPMode (which is a Virtual Machine version of WinXP) to run the 16-bit Windows apps (but not all of them work). They took XPMode out of Windows 10 when they released it.


John

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