My Toshiba Satellite A105-S4324 was having similar problems 3 months after I had purchased it. The Multi-Drive was recognizing all CDs as blank, and the DVDs were only recognized after I uninstalled the Matshita UJ-841S driver, then reinstalled it with version 1.50 (the latest revision for my Toshiba, running Win-XP). It works completely now, but ONLY AFTER I went to "My Computer", right-clicked the CD/DVD drive, selected "Sharing and Security", selected the "Recording" tab at the top, then check-marked "Enable CD recording on this drive". I don't understand why this should work for me to be able to READ CDs, but it does. Hope this helps someone else out there. Wow, two years with no other solution other than banging the bottom of your laptop below the multidrive (yes, I tried that too, to no avail).