Windows 7: Autoinstall - DVD versus Flash

Wonder if there's someone out there who can help.

I've created a autounattend.xml to install Windows7 completely Zero Touch. Works 100%
It also installs all our programs from a local shared drive. 100%



Integrated in the install, it copies the "Default" user profile to c:\aaa

Thereafter it renames the "Default" user profile in c:\users .. to default.old
Then it copies a "Default" folder from c:\aaa to c:\users\
Finally after some registry tweaks that also runs via a .bat file from c:\aaa, it auto deletes c:\aaa

Created a bootable flash to install and do all of this. Works like a charm. 100%... 100%

Now the problem: If I create a bootable DVD, all works 100%, but somewhere, somehow, the "Default" user profile does not copy correctly. It copies, but with errors on boot and I have to overite it with the "Default" from my working Flash stick.

How is it possible that it will work from Flash, but not DVD.... nothing gets written to it, only read from it.

Hope there's someone out there who has tried or could shed some light.

Regards
AntonD

(Oh,, same story 32 and 64bit)