With 1.59, is it the installer that is giving the error? If os, you might try https://download.glidos.net/Glidos_v1_59_xp.exe (I realise it isn't XP you are targetting, but there's a chance it might work).

For 1.55, try changing the Glidos configuration, under the Dos tab, change Dos Emulation to Windows.

Glidos wrote on 2025-10-10, 13:00:

With 1.59, is it the installer that is giving the error? If os, you might try https://download.glidos.net/Glidos_v1_59_xp.exe (I realise it isn't XP you are targetting, but there's a chance it might work).

For 1.55, try changing the Glidos configuration, under the Dos tab, change Dos Emulation to Windows.

Yes indeed. While running the 1.59 installer, it prompts the error on 98SE. I did try changing the Dos Emulation to Windows for 1.55, but the game doesn't open afterwards. While using the default mode (DOSBOX emulation), it was working the first time. However, during the subsequent times, the DOSBOX window just stalls.

That's strange. Setting "Dos Emulation" to "Windows" is definitely the right choice for running under Windows 98. I'm struggling to think how it might work at all with DOSBox. The communication between the game and Glidos is entirely different under 95/98. Come to think of it, when trying to run under Windows 98, it's probably best to get TR I running in softwere mode first to make sure you have any config correct.

Did you try the XP installer for 1.59? It's not really specific to XP. It's my old bespoke Glidos installer, from before i swapped to the standard inno setup.

Where are you finding Glidos 1.55? I don't see it on download.glidos.net. Not sure why it isn't there. I tended to keep all old versions.

Also wasn't getting Glidos 1.59 to run in Windows 98, just froze on the DOS screen, although randomly but rarely the game would start up. Seems there may be a typo in /OVL/pipe.c for glide2x.ovl that prevents the OS from being detected correctly, using jp instead of jmp in two places. I'm rusty on my assembly but this was AI's catch, and changing these does appear to make it work.

Wow! Interesting. The explanation doesn't sound quite right. Back in the days when 98 was current, it worked reliably, and I'm pretty sure that file hasn't been altered since that era. But having it work after making the change is compelling evidence. If you can get a definitive fix, I'll work it into a new download version.

To me the explanation does make sense, since why would you be interested in the parity flag in this context? This is the code, you tell me:

1#pragma aux detect_os =          \
2    "mov cx, es"                 \
3    "mov dx, di"                 \
4    "mov ebx, 0h"                \
5    "mov eax, 1684h"             \
6    "int 2fh"                    \
7    "mov bx, es"                 \
8    "or bx, di"                  \
9    "jz nt"                      \
10    "mov bx, es"                 \
11    "sub bx, cx"                 \
12    "sub dx, di"                 \
13    "or bx, dx"                  \
14    "jz dosbox"                  \
15    "mov eax, 0h"                \
16    "jp exit"                    \
17"nt: mov eax, 1h"                \
18    "jp exit"                    \
19"dosbox: mov eax, 2h"            \
20"exit: mov es, cx"               \
21    parm [edi]                   \
22    modify [eax ebx ecx edx edi] \
23    value [eax];

So it's DOSBox if !bx|dx, otherwise Win 98, but actually nevermind if bx|dx from a few instructions ago had an even number of 0s we fall through NT with the same parity check and into DOSBox again. Doesn't sound right.

The code has no license as far as I can tell, so a definite fix would have to come from you.

Oh yeah. 😀 Sorry for doubting - I think you're right. It is the sort of mistake I can imagine making. Strange not to have picked it up at a later date, though. I'll see if I can find the tools I used to build this.

Possibly I should add a licence file too. I'm happy for people to do whatever they want with it. BSD maybe.

So maybe this will work better: https://download.glidos.net/Glide2x-ovl-vvbeefix.zip

That works, thanks. Verified by testing with default files => doesn't work (freezes after DOS4/GW banner with Screamer 2), adding new OVL => works.

I also notice now that if I install sound drivers then the default Glidos works as well. If I disable the audio device from the BIOS then the default Glidos goes back to not working, but works again with the new OVL. It's not an audio issue since the OVL change doesn't touch on audio, and in any case I have the audio options off in Glidos, but since memory addresses were involved in the parity flag then presumably on my system at least having audio enabled has a lucky effect on the memory layout. Or maybe this is typical in Windows 98.

If Screamer 2 works or starts to work then Screamer Rally also and Screamer is S3D game.

Came across an instance where the original OVL didn't work under the condition that sound is enabled. Booted into Windows 98, ran Glidos, froze at DOS4/GW. Restarted Glidos a few times, same issue. Replaced the OVL with the fixed one, worked. Put the original OVL back, didn't work, then the fixed OVL, worked. After rebooting, the original OVL started working again as well.

I'm running this on a Pentium 4 system. Maybe later platforms if not later versions of Glidos are more likely to trigger the bug.