How things can go wrong with a USB device: an IRQ conflict
Problem
A SanDisk SDDR31 Imagemate USB card-reader works on a notebook computer running Windows XP, but when connected to a desktop PC running Windows 98 SE, a blue screen of death appears within 15 seconds of the device being connected to a USB hub, even though the software was loaded according to the instructions, followed by the installation of the latest device drivers from SanDisk.
The error message reads: "A fatal exception OE has occurred at 0028:c15b0527 in VXD APIX(01)+00003207."
Possible solutions
Any fatal exception OE that has a segment address of 0028 strongly suggests an interrupt request (IRQ) conflict, with it being most likely that the USB device is sharing an IRQ, and the device drivers are not properly programmed to enable IRQ sharing, which, of course, both Windows 98 SE and Windows XP support.
If you don't know anything about interrupt requests, and IRQ sharing, read this Q&A on this page: A new USB 2.0 adapter card makes my computer crash: a problem with IRQ sharing - or enter the terms (within double quotation marks) in the Google search box at the top of this page.
The first thing to do is in such a case is to check (or check again) for driver updates. If the latest drivers are loaded they should support IRQ sharing properly. If the problem still exists, the most likely cause is that an application has installed a conflicting version of the Apix.vxd file - the VXD file named in the error message.
Programs from Adaptec, Roxio Easy CD, and Direct CD are notorious for installing their own versions of the Apix.vxd file in the C:\Windows\System\IOSUBSYS folder. If any of these programs are installed on the system, upgrading them to the latest versions will allow you to restore the original Windows 98 versions of Apix.vxd and Wnaspl32.dll into this folder. This is because the latest versions of these programs don't share the Windows versions of these files - they place their own versions in their programs' folders.
The original Windows files should still be in the same folder and have been renamed with a .bak (backup) extension. If so, rename the existing Apix.vxd and Wnaspl32.dll to Apix.adp and Wnaspl32.adp, and then change the .bak extension on the backup files to .vxd and .dll respectively.
If the .bak versions of these files don't exist, then use the right mouse button to click on the Apix.vxd file, click Properties and check under the Version tab. If the Company name is listed as Adaptec instead of Microsoft, the Adaptec version of both of theses files have to be replaced with the Microsoft versions from the Windows 98 CD.
The easiest way to replace the files in a Windows 98 /98 SE system is to follow this path Start => Run - and enter sfc (to run the System File Checker). Choose the option that allows a single file to be extracted from the Windows CD, and enter the file's name in the search box. The source and destination folders do not have to be specified, because the SFC already knows them. Rebooting the system should solve the problem.
If there is still a problem, try conducting a Google Groups search by entering the the name of a newsgroup such as alt.windows98 in the first search box, followed by the error message (or part thereof) within double quotation marks in the second search box that comes up.
Note that the System File Checker still exists in Windows XP. But, for some reason, it has been well hidden. There is no information on it in Help and Support. It is run from the Command Prompt, which is opened by entering cmd in the Start => Run box. Enter the command sfc /? to bring up a list of the commands and switches that can be used with it.
It can be a useful problem-solving utility if you know how to avoid the pitfalls, which are provided on this page.
SFC Explained -
http://www.westelcom.com/users/rogersr/sfc.htm
If you want to use SFC, you should have a certified Windows CD - not a System Recovery CD of the kind that comes with many brand-name computers instead of a Windows CD - because SFC makes use of it.
