incorretly formatted dvds

Im having a problem with a few dvds i burned with nero yesterday. for some odd reason they now refuse to play even though they worked perfectly straight after i burned them.

windows says they are incorrectly formatted. is there any tool out there to save the data on these dvds or format them correctly without destroying the data?

I have since updated nero and the problem seems to have stoppped.

Are you talking about DVD -RW 's?

no they are dvd -r