Slowly getting desperate...
I recently installed new drivers for my nForce2 chipset. After that, EAC won't see my CD and DVD drives when I set it's interface to the "Installed external ASPI interface". When I set it to "Native Win32 interface for Win NT/2000/XP" and restart it, it sees the drives again.
I've had a similar problem some time ago, but I solved it by installing the ForceASPI interface... now even that doesn't work.

How do I make it see the drives while using the ASPI interface?
Any help or idea would be appreciated.

[edit: typos]

Why not use Native Win32 interface for Win NT/2000/XP?

You shouldn't have installed the nVidia IDE drivers (these are known to cause troubles with missing recognition of CD/DVD drives). I had a very similar problem ... after installing IDE drivers from nVidia, Plextools didn't recognize the Plextor drives ...

My advice would be to exchange IDE drivers for standard Microsoft drivers ... using these, you'll get a stable and working system.

Oh, BTW ... there is no noticeable difference between SPTI (native interface) and ASPI within EAC.

How do I do that? And why do the nVidia drivers cause issue?

I installed the nVidia drivers bcos M$ drivers caused an annoying issue - after some time, the secondary slave drive (my PleXWriter 16/10/40A) refused to communicate through DMA. The issue got solved this way (but it caused this one, it seems...)

In device manager under ATA/ATAPI controller, you can select 'driver update' for your controller (righ click - driver update) and select the 'M$ standard driver' after switching to 'user defined' and 'show all' ... then reboot and everything should be fine.

For your plextor problem ... did you try to switch the drive to dedicated 'master' (not cable select) ? Plextor drives don't like to be slaves from my experience ...

Yes, I never leave the "Cable select" option... I've had this problem since I installed WinXP, despite I even changed 75% of my hardware from that time.
The communication mode just changes from DMA to PIO mode, and even though I set it to "DMA if available" and restart, the mode stays PIO. When I installed the nForce drivers, the DMA was on again (yay).

OK, I'll go try setting the M$ driver now.

Hmm. Where can I see a comparation between the two interfaces? Isn't the ASPI interface better?

I have ripped some 1000+ CD's in native mode ... no problem at all

Does your Plextor have a DMA jumper on the backside ? Setting this active will put your drive in Multiword-DMA which should work without problems (you'll get a lower CPU usage during access but not the transfer rates that are possible with UDMA ... but a 16x10x40x drive runs fine with PIO4 transfer rates anyway).

Have you ever tried putting the WNASPI32.dll into your EAC directory?

Works for me. (I use the one delivered with Nero - see your Nero folder)

Not if it doesn't work and the Native Win32 Interface does.

There seems to be a common misconception that people must install the (Adaptec/Nero) ASPI layers with EAC. This simply isn't the case. DO NOT install them (Nero is safe) if EAC works without them, you only risk breaking other things and gain little, if anything.

If you had a scratched CD that refused to load properly in your drive, WinXP turns DMA to PIO mode for this drive.
There's a trick you can try to fix it, may it happen again.
Locate the following key in your registry:
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E96A-E325-11CE-BFC1-08002BE10318}]
It should stand for your "Standard Dual Channel PCI IDE Controller" (M$ driver).

You should then find these subkeys labelled '0000', '0001', etc
Locate the one matching your drive IDE channel: "Secondary IDE Channel" probably.
Add this DWORD: "ResetErrorCountersOnSuccess"=dword:00000001
(A subsequent inserted "good" CD will reset the internal counter)

You must delete both values/datas: "MasterIdDataCheckSum" and "SlaveIdDataCheckSum"
You can now reboot and DMA transfers should be available again.

First of all, drives falling back from UDMA to PIO modes is caused by damaged IDE ribbons - buy a new 80-conductor cable.
From my experience the newest nVidia IDE drivers are fine, there were problems with older versions so just make sure that you have the newest ones.
If EAC recognizes your drives with SPTI only then use SPTI, there's nothing wrong in it.

Tried. Doesn't work.

If you've replaced 75% of hardware on the same XP install, you have more than just ASPI issues. Time for a reinstall of windows.

Don't worry, did that a lot of times in the meantime (I know that fact - learned the hard way )