That is correct.
OP: have you tried that DVD in another computer? Even in several different computers. There can be certain issues with CDs and DVDs that allow them to read in some drives and not in others.
Any scratches, smudges, spots, etc. on the DVD? They are not usually a problem, but if there is a bad one in the right place, it is a big problem.
Is this a re-writable DVD? People sometimes interchange the names of the types of DVDs. Some are write once, others are erasable, like a hard drive. Does it say "rewritable" on the DVD? Does it really say DVD-RW on it or DVD-R? Huge difference.
Also, some drives have a problem with a DVD or CD that is not "finalized."