Can write CD-R CANNOT write CD-RW. Why?

[---tom---]

I can not understand why I can burn CD-R disk but when I try to burn something on to a CDRW disk it seems to be burnt until I go to explorer and see that the disk is still blank!
I have tried Roxio, Nero and burning from windows explorer.
I have burnt CD-RW disks at work and can read them ok.
Can anyone help?


CD is running at Primary IDE Channel device 0 UDMA mode 2

Media I have tried are Sony CD-RW650 (4x) and TDK CD-RWXG (4x)

Sony CRX300A/E DVD(read)/CD-RW combo 48x/24x/48x/16x Firmware KYS1
AMD 2500+
ASUS A7N8X Dlx
2 x 512meg DDR crucial
Maxtor 120Gig SATA
Windows XP Pro SP1
MSI FX5200