Not trying to do the USB driver would have probably been a good idea. Trying with a simpler driver, the Realtek RTL8139C+, which I can emulate in 86box, I still run into an obstacle. When I look in the cab file, and the layout, I should have the requisite INF file for the driver copied over to the C:\Windows\INF folder. But it seems to be missing. The CAT file is in the CATALOG3.CAB file, and everything is right, so far as I can tell, in LAYOUT*.inf, COPY*.inf and SUBASE.inf. I am putting the two INF files in PRECOPY2.CAB, maybe that is an error in judgement, entirely likely the problem is PEBKAC, I will try again later.

I at least didn't kill the Windows 98 setup this time by replacing files!

I also tried adding drivers for an ADAPTEC ASC-39160, which I have handy and in a real hardware setup that I can test. I am not sure that worked either, but I think I should probably try to get the Realtek drivers working first, then try real hardware drivers.

I've spent some time automating Windows 9x installs, with some Python code assembling the files, but I avoided doing what you're doing because modifying .CAB files just seems too painful! I only copied some drivers in bsetup.inf in a way that I have to set [System] Display="..." to force it to use the driver. Good enough for my "build an install directory for this specific machine", but not good enough if you want a generic kind of install that will work on multiple machines.

Instead of what you're doing, have you considered running driver installers automatically after Setup is done? Obviously that's not a great solution if the driver is for the disk you want to install onto, for example, but I imagine USB drivers are the kind of thing you could install later.

If you want DOS-based USB drivers, go to https://dosprograms.info.tt/indexall.htm then go to the Utils section, and you will find some USB drivers for DOS. I recommend copying the Windows CD to your hard drive then running it from there, as the driver is Shareware and will stop working after a short period of time.

Instead of what you're doing, have you considered running driver installers automatically after Setup is done? Obviously that's not a great solution if the driver is for the disk you want to install onto, for example, but I imagine USB drivers are the kind of thing you could install later.

I might just do that, I think I would have to re-add the devices in Device Manager by hand that way. I found sweetlow's USB packages, and those look a bit more promising for integration to me (fewer files at least, and hopefully won't bork the setup).

I also realized, I had not added the network card inf to SETUPPP.INF, so I wonder if that explains the failure on the network card addition? I am purely doing it because 86box has that card, and so I can test more conveniently whether it worked.

I am rebuilding the cabs now to see.

modifying .CAB files just seems too painful!

I am really starting to think that might be the case, resealing the cabs using rloew's slipstream tool in 86box is fairly slow.

If you want DOS-based USB drivers, go to https://dosprograms.info.tt/indexall.htm then go to the Utils section

Interesting, I didn't know about those, that is really neat. Is there no way to pay for them at this point? I mostly just want USB 2.0 cards to kind of work out of the box in Windows, I like to use flash drives for file transfer between new and old. I also have a Pentium that I have DOS 6.22 installed on, and that would be pretty handy.

For the Windows version, Google "nusb36e.zip." As for DOS, just copy some files at a time, reboot your system then copy some more, as the drivers will stop working after a while, as they're Shareware. As for registering, I don't know either: I just looked and saw no information on registering. Sorry. 🙁