crazii wrote on 2026-06-28, 06:23:

It seems a IO problem. e.g. INT13h error causing command.com not loaded properly. You may want to comment out your lines in CONF […]
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shawnmos wrote on 2026-06-26, 19:00:

I am getting "The following file is missing or corrupted: Command.com" after loading JemmEx. I am using an Inspiron 2200 laptop with Intel 915 chipset and AC'97 audio. Any ideas?

It seems a IO problem. e.g. INT13h error causing command.com not loaded properly.
You may want to comment out your lines in CONFIG.SYS, e.g. add REM before DEVICE=JEMMEX.EXE and other lines to find out which device driver is causing the problem.
Also disabling option ROMs and USB legacy supports in BIOS settings may help.

I assume you don't use VDPMI but JEMMEX, because the two programs are not compatible. So another options is try VDPMI, but no guarantee that it will work, I will post the link in the OP.

I get the error when loading JEMMEX regardless what else is loading in config.sys. I decided to give QEMM v9 a try as well but it just hangs. When I try to do the memory optimization feature of QEMM I end up getting the same command.com error. I tried using the JEMMEX /load command after booting and after it loads I get a drive not ready or general failure reading drive c (I can't remember which exactly). I'll take a look at the BIOS too but since it's a base model Dell I don't think there was much in the way of settings. SBEMU does work without JEMMEX and real mode, but I was trying to get Keen 4 working and I think it needs real mode.

Thanks for your help. I'll give the VDPMI version a try next.

shawnmos wrote on 2026-07-02, 21:43:

crazii wrote on 2026-06-28, 06:23:

It seems a IO problem. e.g. INT13h error causing command.com not loaded properly. You may want to comment out your lines in CONF […]
Show full quote

shawnmos wrote on 2026-06-26, 19:00:

I am getting "The following file is missing or corrupted: Command.com" after loading JemmEx. I am using an Inspiron 2200 laptop with Intel 915 chipset and AC'97 audio. Any ideas?

It seems a IO problem. e.g. INT13h error causing command.com not loaded properly.
You may want to comment out your lines in CONFIG.SYS, e.g. add REM before DEVICE=JEMMEX.EXE and other lines to find out which device driver is causing the problem.
Also disabling option ROMs and USB legacy supports in BIOS settings may help.

I assume you don't use VDPMI but JEMMEX, because the two programs are not compatible. So another options is try VDPMI, but no guarantee that it will work, I will post the link in the OP.

I get the error when loading JEMMEX regardless what else is loading in config.sys. I decided to give QEMM v9 a try as well but it just hangs. When I try to do the memory optimization feature of QEMM I end up getting the same command.com error. I tried using the JEMMEX /load command after booting and after it loads I get a drive not ready or general failure reading drive c (I can't remember which exactly). I'll take a look at the BIOS too but since it's a base model Dell I don't think there was much in the way of settings. SBEMU does work without JEMMEX and real mode, but I was trying to get Keen 4 working and I think it needs real mode.

Thanks for your help. I'll give the VDPMI version a try next.

I am getting this crash unfortunately

shawnmos wrote on 2026-06-26, 19:00:

I am getting "The following file is missing or corrupted: Command.com" after loading JemmEx. I am using an Inspiron 2200 laptop with Intel 915 chipset and AC'97 audio. Any ideas?

I have the same problem with my Precision M70, which uses the same chipset. I’m no expert, but it seems JEMMEX messes up the communication between the system and the HDD on these older Dell laptops. I found a workaround: placing the XHDD caching driver after JEMMEX in config.sys.

http://optimizr.dyndns.org/dos/drivers.html

I observed similar behavior on my GB MB with P67 chipset. When the HDD is attached to SATA3 port it has some weird issues in V86 mode, I have special version of XHDD that resolve it. When the HDD is attached to SATA2 port it works OK. I have SATA in IDE compatible mode and USB legacy disabled.

Thanks for this project!. I've been using the latest experimental build with VDPMI. Works better than the one with HDPMI in my computer (Intel Atom N280, 1 GB RAM, Intel HDA, MS-DOS 6.22).

This are the lines I use to load SBEMU:

1DEVLOAD.COM VDPMI.EXE /EMS
2SBEMU.EXE /I5 /T6 /O1 /VOL60 /K44100

This is my CONFIG.SYS:

1DOS=HIGH,UMB
2DEVICE=C:\DOS\SETVER.EXE
3DEVICE=C:\DOS\HIMEM.SYS /TESTMEM:OFF
4DEVICE=C:\UMBPCI\UMBPCI.SYS
5DEVICEHIGH=C:\DOS\POWER.EXE ADV:MAX
6COUNTRY=034,,C:\DOS\COUNTRY.SYS
7DEVICEHIGH=C:\DOS\DISPLAY.SYS CON=(EGA,,1)
8FILES=30
9STACKS=9,256

I get some errors:

• Loading VPDMI I get the following warning: 64K page frame unavailable. limited page frame size: 32K
  Running MEM shows 56.364K XMS in use and 4.096K total and free EMS memory, but most of games seem to work fine.

• PC Speaker does not work in any game I've tried. Without SBEMU all work fine.

• Visual Player 2.0 (MOD audio player) does not load and shows this error: ERROR: 8 Bit DMA not detected, please try again...

• Disney's Aladdin plays fine but with corrupted graphics at the bottom of screen.

• Links 386 Pro crashes with the following message.
  Spoiler

  386|DOS-Extender 4.1 -- Copyright (C) 1986-92 Phar Lap Software, Inc.
  Serial Number DE1-9163
  VDPMI Client32 "LINKS386.EXE" Protected Mode Exception: 0d, Error code: 00
  EAX:00000000 EBX:00001098 ECX:00001000 EDX:00020000 ESI:0050f804 EDI:00000c40
  EBP:00000c4c DS:00e7 ES:0107 GS:0107 FS:0107 CR2:00000000 VISR=0000
  SS:ESP:0107:0009d8ee CS:EIP:00ff:000005df EFLAGS:00210202 VM=0 IF=1 VIF=0 VIP=0
  DS: base: 0000ebd0 limit: 0000ffff ES: base: 00000000 limit: 000fffff
  SS: base: 00000000 limit: 000fffff CS: base: 00019460 limit: 0001ffff
  CS:EIP: 26 89 46 fc 67 a1 b8 1c 26 89 46 f8 26 89 4e f4
  SS:ESP: a5a501fe a5a5a5a5 a5a5a5a5 a5a5a5a5 a5a5a5a5 a5a5a5a5 a5a5a5a5 a5a5a5a5
  a5a5a5a5 a5a5a5a5 a5a5a5a5 a5a5a5a5 a5a5a5a5
  VDPMI Server Exception: 0d, Error: 0014
  EAX:00000000 EBX:00001098 ECX:00001000 EDX:00020000 ESI:0050f804 EDI:00000c40
  EBP:00000c4c DS:00e7 ES:0107 GS:0107 FS:0107 CR2:00000000 VISR=0000
  SS:ESP:0020:0000efc8 CS:EIP:0010:0050d1da EFLAGS:00210002 VM=0 IF=0 VIF=0 VIP=0
  DS: base: 0000ebd0 limit: 0000ffff ES: base: 00000000 limit: 000fffff
  SS: base: 008ff000 limit: 00524fff CS: base: 008ff000 limit: 00524fff
  CS:EIP(0002:000021da): cf 00 00 00 00 00 50 8b 44 24 04 89 44 24 bc 58
  SS:ESP: 007006f4 03720016 007006f4 007006f4 f000ff54 00000107 000000e7 00000107
  00000107 000005df 000000ff 00210202 0009d8ee
  Exiting with error: 800d0014

  Pinball Illusions and Virtual Pool crashes with similar messages.

• Micro Machines plays ok but the computer hangs on exit.

• World Class Leader Board crashes when loading title screen.

• Several other games work fine: Duke Nukem 3D, F29 Retaliator, IndyCar Racing II, Lemmings, Loom, Prince of Persia 2, The Lion King, The Lost Files of Sherlock Holmes, WarCraft II, Zoop.

How would I get utilities like CPUSPD to work with VDPMI? It just gives me a SIGSEGV error when running it.

VDPMI as V86 monitor prevents DOS apps acessing some critical structures in memory (is more restrictive than others - EMM/JEMM/QEMM386 etc.). As I wrote before, my CPUID, MTRRLFBE, SMB, etc. are not the only apps that manipulates GDT/LDT to setup a callgate...

Found a temporary workaround to this issue. (Until a better solution exists)
Since you can manually run VDPMI, I made it so that I run the CPU slowdown tool before starting the VPDMI server.
Like this

CPUSPD ...
VPDMI
SBEMU /vmpu

sergio_prado wrote on 2026-07-12, 02:10:

shawnmos wrote on 2026-06-26, 19:00:

I am getting "The following file is missing or corrupted: Command.com" after loading JemmEx. I am using an Inspiron 2200 laptop with Intel 915 chipset and AC'97 audio. Any ideas?

I have the same problem with my Precision M70, which uses the same chipset. I’m no expert, but it seems JEMMEX messes up the communication between the system and the HDD on these older Dell laptops. I found a workaround: placing the XHDD caching driver after JEMMEX in config.sys.

http://optimizr.dyndns.org/dos/drivers.html

That sounds very promising! The link doesn't seem to work. Is there another place I can grab it from?

shawnmos wrote on 2026-07-16, 17:05:

That sounds very promising! The link doesn't seem to work. Is there another place I can grab it from?

https://web.archive.org/web/20260702024146/ht … os/drivers.html

Did a test on my main gaming rig (X570) where SBEMU might be of some relevance... it works well, but I noticed something off. I'm using the VDPMI version from GitHub.

While my X-Fi Titanium HD can be used by SBEMU using the CTXFI driver and it works as expected, there's a constant gray "ctxfiirq x" line being printed every a few seconds, with "x" starting from 2000 and increases by 2000 on every output. This output can mess up text mode interfaces while mostly harmless in graphical modes (in game). No such behavior observed with Intel HDA. Both X-Fi and HDA work with SBEMU on my system.

DIGPAK's SFX portion (SETD) doesn't seem to work correctly. It detects the presence of Sound Blaster, but hangs on testing. Music portion (SETM) works correctly for both FM and MIDI (using soundfont). In case of CTXFI, even after SETD hung on testing the sound driver, the "ctxfiirq x" lines continue to be printed.

Tested these games:
- Skyroads (works)
- Spear Resurrection (Wolf3D engine, works)
- Duke Nukem 3D (SETUP part works, SFX and Music tests pass, Reverse Stereo needs to be checked for correct channel output. Hangs with screeching noise a few seconds after launch, during opening cinematic)
- Jazz Jackrabbit (works correctly ingame, but I get a VDPMI Server Exception 0e, Error 0002 on exit).
- Titus the Fox (needs EGAFIX for my Ampere video card. Does not work, crashes and hangs the system with first a VDPMI VM86 Exception 0d Error 0000 followed by a VDPMI VM86 Exception 06 Error 0000)
- Bio Menace (works, needs EGAFIX for my Ampere video card, and additionally /LATCHPEL to fix scrolling issues)
- Rise of Triad (works without crashes, but the sound seems sluggish)
- Tetris Pro by Michiel Ouwehand (works, the music seems sluggish by default but will play normally when I move mouse cursor. The game is not intended to be played in V86 mode and will warn you if detected V86, but will still allow the game to run.)
- AstroFire and TerraFire (works in SETUP, but I get a constant, screeching noise ingame and sound does not actually work there. DOS4GW)

EDIT: Turned out there was already an issue about this. The author of the issue has since closed it suggesting rerouting debug log to serial, which I've no idea how to do with official releases, and my board doesn't really have any standard serial port exposed.

EDIT 2: Did additional tests using HDA instead of CTXFI (both works, but I'd hope the log spam with the letter can be fixed eventually). Real mode games (V86) work better in overall while Protected mode games are hit-or-miss.

shawnmos wrote on 2026-07-02, 23:30:

I am getting this crash unfortunately

The attachment 20260702_192356.jpg is no longer available

Oops, I think it's the same underlying reason that JEMM and VPDMI doesn't work, the different outcomes is due to different implementations. but you may want to try the XHDD driver mentioned by others.

ntalaec wrote on 2026-07-15, 10:30:

Thanks for this project!. I've been using the latest experimental build with VDPMI. Works better than the one with HDPMI in my c […]
Show full quote

Thanks for this project!. I've been using the latest experimental build with VDPMI. Works better than the one with HDPMI in my computer (Intel Atom N280, 1 GB RAM, Intel HDA, MS-DOS 6.22).

This are the lines I use to load SBEMU:

Copy code to clipboard

1DEVLOAD.COM VDPMI.EXE /EMS
2SBEMU.EXE /I5 /T6 /O1 /VOL60 /K44100

• Loading VPDMI I get the following warning: 64K page frame unavailable. limited page frame size: 32K
  Running MEM shows 56.364K XMS in use and 4.096K total and free EMS memory, but most of games seem to work fine.

• Disney's Aladdin plays fine but with corrupted graphics at the bottom of screen.

Thank you for the test and feedback!

Aladdin require 64K EMS page frame and you can try /EMSX instead of /EMS, which have 64K page frame. You're running VDPMI in command line so /EMSX is not fully tested on that scenario. or you can try to disable some option ROMs or USB legacy support in you BIOS to make enough upper memory.

I will try to figure out the other compatibility issues.

LSS10999 wrote on 2026-07-18, 05:07:

Did a test on my main gaming rig (X570) where SBEMU might be of some relevance... it works well, but I noticed something off. I' […]
Show full quote

Did a test on my main gaming rig (X570) where SBEMU might be of some relevance... it works well, but I noticed something off. I'm using the VDPMI version from GitHub.

While my X-Fi Titanium HD can be used by SBEMU using the CTXFI driver and it works as expected, there's a constant gray "ctxfiirq x" line being printed every a few seconds, with "x" starting from 2000 and increases by 2000 on every output. This output can mess up text mode interfaces while mostly harmless in graphical modes (in game). No such behavior observed with Intel HDA. Both X-Fi and HDA work with SBEMU on my system.

DIGPAK's SFX portion (SETD) doesn't seem to work correctly. It detects the presence of Sound Blaster, but hangs on testing. Music portion (SETM) works correctly for both FM and MIDI (using soundfont). In case of CTXFI, even after SETD hung on testing the sound driver, the "ctxfiirq x" lines continue to be printed.

Tested these games:
- Skyroads (works)
- Spear Resurrection (Wolf3D engine, works)
- Duke Nukem 3D (SETUP part works, SFX and Music tests pass, Reverse Stereo needs to be checked for correct channel output. Hangs with screeching noise a few seconds after launch, during opening cinematic)
- Jazz Jackrabbit (works correctly ingame, but I get a VDPMI Server Exception 0e, Error 0002 on exit).
- Titus the Fox (needs EGAFIX for my Ampere video card. Does not work, crashes and hangs the system with first a VDPMI VM86 Exception 0d Error 0000 followed by a VDPMI VM86 Exception 06 Error 0000)
- Bio Menace (works, needs EGAFIX for my Ampere video card, and additionally /LATCHPEL to fix scrolling issues)
- Rise of Triad (works without crashes, but the sound seems sluggish)
- Tetris Pro by Michiel Ouwehand (works, the music seems sluggish by default but will play normally when I move mouse cursor. The game is not intended to be played in V86 mode and will warn you if detected V86, but will still allow the game to run.)
- AstroFire and TerraFire (works in SETUP, but I get a constant, screeching noise ingame and sound does not actually work there. DOS4GW)

EDIT: Turned out there was already an issue about this. The author of the issue has since closed it suggesting rerouting debug log to serial, which I've no idea how to do with official releases, and my board doesn't really have any standard serial port exposed.

EDIT 2: Did additional tests using HDA instead of CTXFI (both works, but I'd hope the log spam with the letter can be fixed eventually). Real mode games (V86) work better in overall while Protected mode games are hit-or-miss.

Thank you!
There seems a lot more compatibility issues than expected. 🤣. I will remove the log spam for CTXFI on next release.

crazii wrote on 2026-07-25, 04:24:

Thank you for the test and feedback!

Aladdin require 64K EMS page frame and you can try /EMSX instead of /EMS, which have 64K page frame. You're running VDPMI in command line so /EMSX is not fully tested on that scenario. or you can try to disable some option ROMs or USB legacy support in you BIOS to make enough upper memory.

I will try to figure out the other compatibility issues.

Thanks! Aladdin now works without issues. VDPMI causes a lot of problems for other software in my computer so I don't load it in CONFIG.SYS. I have found games which don't work unless VDPMI is loaded with DEVLOAD, which seems to work fine. Some games crash without EMSX parameter and others crash with it.

I have found other weird issues:
Warcraft 2: does not load (Sound Blaster not found) unless I ran other game before (like Aladdin).
Duke Nukem 3D: sounds in 16 bit are distorted, 8 bit sounds play fine. Music plays fine.
Descent 2: 16 bit sound not available. 8 bit sounds are distorted during gameplay. Music plays fine.

To mitigate the issuse with HDD and V86 mode I use this special version of XHDD (thx to Jack).
It must be loaded twice in config.sys like this:

[4]
DOS=HIGH,UMB
REM XHDD must be preloaded before switch to V86 mode
DEVICE=C:\DOS\PLUS\XHDD.SYS
DEVICE=C:\DOS\HIMEMSX.EXE /METHOD:FAST /NUMHANDLES=64
DEVICE=C:\DOS\JEMM386.EXE SPLIT FASTBOOT VERBOSE
DEVICEHIGH=C:\DOS\PLUS\XHDD.SYS /S64 /H
DEVICEHIGH=C:\DOS\PLUS\XDVD2.SYS /D:MSCD000 /H
STACKS=9,256
BUFFERS=15
LASTDRIVE=Z
FCBS=4,0
FILES=80
SHELL=C:\COMMAND.COM C:\ /E:1536 /P