Comments on: Why 16bit Applications Cannot Run on Windows 64bit

By: Ken Knopfli

Ken Knopfli — Mon, 02 Nov 2009 08:56:31 +0000

I know of two dentists that use a DBase/Clipper based patient system. And I still like to play with Borland’s Eureka.

We have machine control systems that run on 16 bits. I have no idea who is going to rewrite those, nor who is going to pay for, basically, no additional functionality.

By: Christian Wimmer

Christian Wimmer — Sat, 31 Oct 2009 12:37:55 +0000

I wonder if the XP VM Mode in Win7 is capable of running 16bit apps seamlessly on Windows 64bit?

By: murphy

murphy — Fri, 30 Oct 2009 22:20:27 +0000

I started Turbo Pascal for Windows in Windows 7 32bit recently. Sure i’m not using it really… It was only a test.

By: Thomas Mueller

Thomas Mueller — Fri, 30 Oct 2009 22:11:24 +0000

The only 16 bit Windows program that I still use is DBase. But there are quite a few DOS programs.

By: Anthony Frazier

Anthony Frazier — Fri, 30 Oct 2009 20:41:19 +0000

The primary, overriding reason is that x86-64 CPUs running in long mode cannot switch into virtual 8086 mode, which is what the NTVDM and current 16-bit support are based on.

MS would have to rewrite the NTVDM and 16-bit support in order to get them to work in 64-bit Windows by virtualizing much of the CPU, and they’d still have massive back-compat issues.

Or they could just point at Virtual PC and friends and call it good enough, which makes a hell of a lot more sense than trying to reimplement that stuff.

By: Warren

Warren — Fri, 30 Oct 2009 19:34:12 +0000

I think VMWare/VirtualPC box running Windows 98 would give you sufficient Dos/Win3/Win98 app compatibility on Windows 7 or Windows Vista 64bit.

Warren