Same problem - but this worked well for me
I had the same error message when trying to load vista business upgrade edition (4 CDs) - when I tried to create using Express install. Same as jay-dubb it bypassed the first window (asking for language currency etc) and also when copying files it would reach 100% with only one CD (when I installed it on a PC it required all 4 CDs). I googled the problem and found a solution on the microsoft website (
http://forums.microsoft.com/TechNet/ShowPost.aspx?PostID=1238946&SiteID=17 ). to cut a long story short Here's how I did it.
1. Create a new parallels setup using "typical install"
2. Copied the contents of Vista business upgrade CD 1 onto a folder on my computer I labelled "VISTA" - this folder should contain several files and folders including a folder called "Sources" (which contains a file called install.swm - the culprit !!)
3. Copy the contents of CD 2 (which only contains a file called "install2.swm") into VISTA\Sources (ie the folder called Sources)
4. Copy the contents of CD 3 (which only contains a file called "install3.swm") into VISTA\Sources
5. Copy the contents of CD 4 (which only contains a file called "install4.swm") into VISTA\Sources
6. Make a DVD (using Toast or otherwise) with the CONTENTS of the VISTA folder (ie. it should look identical to the CD 1 except have 3 extra files in the Sources folder) - it came out at 1.9GB for me.
7. Install Vista using the DVD
It worked a treat for me and had the advantage of not requiring swapping of CDs during install.
I'm not sure about the 5 CD version - presumably CD 5 may contain a file called install5.swm - in which case adding this to the source file would theoretically work (but I'm only guessing)
As an interesting aside - which I thought I would also share. My vista business upgrade was not a bootable version. I thought that was that as parallels wouldn't boot from it. But I have an old windows 2000 CD. I got round this by creating a new parallels setup telling parallels I was going to instal vista (with typical install) but put in my bootable windows 2000! It installed no problems. I upgraded it to SP4 (but didn't bother installing any parallel tools at this point) - which the vista upgrade CD required. I then put in my upgrade CD and the upgrade then ran smoothly (after using the technique above). I read forums on trying to convert a non bootable vista CD to a bootable one - but this can be bypassed on parallels if you have a bootable windows 2000 operating system CD!! - I'm not sure if other operating system eg win 98 or NT would work. Let me know if they do!
Hope this is of help to someone.