TweakUI had an option to enable/disable this (below website even includes it in a screenshot)
https://www.oldergeeks.com/downloads/file.php … d%20much%20more.

Is there no registry entry I can copy over or something? I'd rather do that, since I don't really see myself needing anything else out of this extra software. I appreciate the recommendation though.

On Device Manager when checking the properties of a CD drive, there is an option to toggle Autorun which is called "Auto insert notification" and it is located in Settings tab.

As mentioned in my opening post, I have that toggle enabled already, yet Autorun is still not working. But thanks.

TweakUI is only a few kb and official (if unsupported) MS product if that worries you. Personally I install it on all my XP and below PC's as it has a few nice settings.
That said it is just a nice GUI to change registry settings and can respect the minimalist approach with installing stuff.

Quick google found this?
https://www.computerhope.com/issues/ch000130.htm

i know this post is old, but anyway i also recently has issues with autorun on my windows 98 SE pc, using Daemon tools on Drive D: and Disc Drive on Drive E: (easier using daemon virtual disc as the first drive otherwise most games will complain about missing cd or audio issues) at first everything was working perfectly fine then for some weird reason the autorun stopped working altogether both virtual drive and the actual physical cd drive. i did not install or run anything that changed the systems config or settings, the games themselves still work fine manually but not automatically. i did fiddle around in device manager and no it didn't fix the problem. but the TweakUI that "chinny22" recommend did actually fix it! now autorun is working again.

it was very easy and simple to install (win98 will not detect it automatically, need to be installed manually) then in the "paranoia" section, check-box the "play data CD's automatically" then click apply then restart pc. afterwards the aurorun should work perfectly fine. it did for me. cause i do not want to re-install Win 98 AGAIN, and playing around with registry is a huge risk.

I don't think Autorun is "associative" in the sense of file type handling in Windows. The system has to search for Autorun.inf on the root, and parse its contents, among which is typically the choice of executable to launch (e.g. Setup.exe, Autorun.exe, Game.exe,...etc).

I just can't see how file associations can break this, unless you reassociated .exe files to something else... in which case you'd have much bigger problems that just Autorun 🙂

That being said, I remember back in the days that Autorun was indeed very easy to break, and I often had it broken until I do another fresh Windows install. I suggest you search for whatever could break Autorun rather than file associations.

One question that could guide you further: when inserting a CD, does the drive's icon change to a custom icon? Or does it stay on the standard CD drive icon?

[Edit: just noticed the OP was years ago... now I look more like an idiot]

when the autorun stopped working it's just standard CD drive icon