Lite-On SOHW-1673 won't burn

I have been using my Lite-On SOHW-1673 for one year without any problem, and the drive reads purchased cd’s and DVD’s normally. But the problem now occurs with CD-R’s.
I have allready burnt several CD-r’s with music, but the other day the files to be burnt maybe exceeded the maximum of the CD-R by some minutes. Normally, Nero 6 warns me that I should not continue, and I follow the warning. But this time there was no warning, and the burning was successfull.
The day after begining a new burning, Lite-On could find no CD-R nor read any burned CD-R.
I checked the CD-R on another computer where I burned it successfully.
What is the problem?
What can I do?
I have attached