1. go to support.dell.com
2. put in your service tag (bottom of your laptop)
3. If you look under warranty information on the left side of the screen, you will find your original equipment list. It will show your CD / DVD Drive type.
4. Go to downloads and the CD / DVD Drives
5. Download the latest firmware for your drive type and install it.
Here is the link to the downloads for your Inspiron Desktop 531:
http://support.dell.com/support/downloads/driverslist.aspx?c=us&cs=08W&l=en&s=bs dv&ServiceTag=&SystemID=INSPDSKTPD531&os=WLH&osl=en&catid=&impid=
Since there are 4 different DVD / CD Models, it is important to download the correct firmware.
Let me know if this helps.
BillH
Let me know if this helps.
BillH