dvd recorder hdd to dvd

Why wont the dvd I recorded on my dvd recorder play on other dvd players ??
I recorded a movie onto the harddrive then later onto a dvd but it wont play on any other player any ideas ??????????

what type of dvd is it?
is it rewritable?
can your dvd player support the type of disk you are trying to use?
what happens when you try to play it does it see the disk at all? do you get sound and no picture?

Also most dvd recorders dont finalise the disk, they leave it open for more data to be written on it later (much like a VHS recorder) so if the disk is not finalised then it can cause problems with other devices trying to play it back. some can cope with it, others simply cant, what usually happens is you get sound and no video for a short while, or it wont detect the disk at all.

Thanks your right I fell for the old didn't finalise trick and now it works ! thanks again !