Wikipedia:Reference desk/Archives/Computing/2019 June 19

= June 19 =

Old PC programs
I'm running a Windows 10 system, and would like to install some old DOS-based programs, and of course that doesn't work. I'm assuming there are some 32-bit or DOS emulators out there which could be added-on. Does anyone have any suggestions of what to use, or just as importantly what not to use? Offhand I'm not seeing an answer in the archives. Thank you! ←Baseball Bugs What's up, Doc? carrots→ 01:50, 19 June 2019 (UTC)
 * DOSBox (official website) does full system emulation - it is a virtual machine that runs a DOS-like operating system. Many old software programs that were designed to run on DOS - rather specifically, on IBM PC compatible systems running MS-DOS - will be compatible with DOSBox, "out-of-the-box."
 * Whether this will meet your needs largely depends on which specific DOS- or DOS-like programs you plan to run.
 * For what it's worth, MS-DOS was not designed to run in 32-bit mode... (see, e.g., DOS memory management, for a technical overview).
 * Nimur (talk) 02:19, 19 June 2019 (UTC)
 * I need to be more specific. A number of these programs use DOS to install Windows 3.1 applications. For example, an old "Jeopardy!" game which can't install as-is within Windows 10. ←Baseball Bugs What's up, Doc? carrots→ 02:32, 19 June 2019 (UTC)
 * Windows 3.1 applications will also not work on Windows 10.
 * You could install Windows 3.1 in DOSBox, though. ApLundell (talk) 02:43, 19 June 2019 (UTC)
 * Ah, that could work. And as far as you know, there are no risks with DOSBox, such as viruses or spyware? ←Baseball Bugs What's up, Doc? carrots→ 02:53, 19 June 2019 (UTC)
 * DOSBox is a well respected tool.  Some older commercial games now come pre-packaged with it.
 * I suppose it's theoretically possible that the software you're trying to run is infected with an old, long-dorment DOS virus, but even so, programs running in DOSBox only have access to the folders you specifically "mount". ApLundell (talk) 03:02, 19 June 2019 (UTC)
 * For example, when I start up DOSBOX, I type "mount C C:\OldGames", and then, when DOS programs think they're writing to C:\ they're really writing to C:\OldGames\.
 * ApLundell (talk) 03:05, 19 June 2019 (UTC)
 * To assuage the concerns about DOSBox itself: it is technically and theoretically possible that DOSBox could be a piece of trojan horse malware; or its developers might be malicious; or you might get an unofficial version from somewhere that was maliciously modified to be harmful; but in practice, provided that you download it from its official distributors, DOSBox is not more risky than any other piece of software, and it is widely used by many enthusiasts for recreational and other purposes.
 * I do not worry that DOSBox will cause serious harm to my general-purpose personal machines; but I wouldn't install any software on the computers for which I must mandate and enforce very strong security guarantees. Most general-purpose personal-computer users can probably accept the low-but-non-zero risk associated with software like DOSBox.
 * Nimur (talk) 05:00, 19 June 2019 (UTC)
 * Thank you all for your help. I'll give it a try. ←Baseball Bugs What's up, Doc? carrots→ 12:10, 19 June 2019 (UTC)
 * It works like a charm. Thank you! ←Baseball Bugs What's up, Doc? carrots→ 02:30, 21 June 2019 (UTC)


 * Are you sure about that? My impression is that Windows 10 is not that different from any version of Windows going back to XP except that NTVDM is probably disabled by default. [//www.groovypost.com/howto/enable-16-bit-application-support-windows-10/] [//answers.microsoft.com/en-us/windows/forum/windows_10-other_settings/how-to-enable-ntvdm-on-windows-10/d6dccaea-2f00-49d7-893c-1c3050ff3077] [//answers.microsoft.com/en-us/windows/forum/windows_10-other_settings/does-32-bit-windows-10-include-the-16-bit/159ebfce-ee4a-451d-9aa0-7f24b8686c71] If you are running the 64 bit version, NTVDM is not supported and so you cannot run 16 bit applications. Probably in part due to significantly added complexity of either running in virtual 8086 mode while in x86-64 long mode or supporting a NTVDM which fully emulates 8086 mode as done with earlier non x86-32 versions of Windows when it mattered more. If you are running the 32 bit version, NTVDM is supported albeit disabled by default on Windows 10. And so you can run 16 bit applications including many 3.1 ones simply by enabling NTVDM. The advances of hardware and software and the OS and the fact that I doubt NTVDM has had much work other than stuff like the security fix a few years back for a long time may mean things are more likely to break than they were before.  NB Windows XP x86-64 is based on Windows 2003 and was released well after the original XP. Still it was branded as XP by Microsoft and so as with Vista, 7, 8, 8.1 and now 10, XP was no different in that NTVDM is provided on 32 bit versions of the OS but not 64 bit versions. (I'm not sure whether some of the Starter and similar versions might have intentionally disabled NTVDM.)  I'm not sure by now whether it makes sense to run Windows 10 x86-32 except in very specific circumstances. But then again I ran Windows XP x86-64 and was never convinced by all the nay-sayers. (Which is not to say there were never problems although many of these were dumb problems simply because some application decided it wasn't allowed to work on Windows 2003 or people still using 16 bit installers in 2005.) Ultimately though, the main point stands that AFAIK there is currently nothing about Windows 10 which means 16 bit applications are not supported other than NTVDM maybe being disabled by default. It's just the classic x86-32 vs x86-64 issue the same for all versions of Windows since XP.  Nil Einne (talk) 05:54, 21 June 2019 (UTC)
 * I had forgotten that there even was a 32-bit version of Windows 10.
 * I believe you're correct that if Bugs is running such a rare beast he may be able to do what he wants without DOSBox. ApLundell (talk) 03:00, 25 June 2019 (UTC)
 * This PC is less than six months old, and if it's running Windows 10 in 32-bit mode, then they pulled a shenanigan on me. ←Baseball Bugs What's up, Doc? carrots→ 15:20, 25 June 2019 (UTC)