Can't play mini DVD RW on computer, why?

As a school project, we were asked to each bring a mini DVD RW disc to record our presentations and write responses after viewing them at home. However, I was unable to play the mini disc on several computers.

The data is clearly burned on to the disc as seen by the rings around it. When I insert the disc into my dvd drive, it says it's empty.

Just wondering why is this so? and how to fix the problem?
Thanks.

 

It may depend on the format in which it was burned. Can you ask someone if it was a UDF disk or whether it was a standard ISO CD? UDF CD's require specialized drivers to read. It would be a poor choice for a class with multiple types of computers to be used.

You could try examining the CD with IsoBuster to see if it finds anything since it can read UDF CD's.