Easy option
This issue was taken up with Microsoft Support but they just went through everything I had tried to cure the problem.
Finally I gave up and took the easy option of installing an IDE DVD R/W drive and it works perfectly. My Blu-ray works with PowerDVD 8 so as long as I don't use it for 'normal' operations I have a solution (of sorts) to this issue of not reading SATA DVD drives.
I believe cdrom.sys has been rewritten for Windows 7 and it doesn't encompass all SATA drives, perhaps the manufacturers will have to write their firmware to comply.
Not an ideal method but at least I now have a fully working system again.
Cheers
Kol
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