Problems viewing DVD recorded with LG LRA-750

I have just bought a LRA-750 and used it to record from VHS.
The recording has been successful but I can view the DVD
ONLY on the LG itself. Neither the computers (iMac, Windows)
nor my other DVD player (Philips DP642) recognize it.
The DVD player says “no-disc” and the computers eject it.
Do you know why ? Maybe I am doing something wrong
in the recording … or are those recordings viewable only
on the LRA-750 ?

Problem solved. I was not finalizing the DVD!!