All attempts to burn a CD fail. When burning from iphoto the message is burn failed unknown error 2147352477. When attempting to burn copies of folders or files or zipped files/folders the whole burn routine goes through and then it notifies me that the disk is corrupted or something. I am using office max CD-r, 700mb disks and they work fine on my ibook, and have previously worked well on the emac. The emac has recently been upgraded to OSX 10.4.11 but I'm pretty sure this started before the upgrade. I have recently run disk utility permissions repair.