LVW 5025GHC+ DVD recordings will not play on PC or other DVDs

[qanda]This thread is about the Lite-On LVW-5025GHC+. Click here to see full specs[/qanda]I have copied tv recordings to disc, but when I try to play them back on PC or other video recorders they will not play. PC states disc blank. They play fine on the LVW.
I am trying to record a whole series and am running out of hard drive space soon.
Please help
Thank you

You need to finalize the dvd (in the lvw 5025ghc), before you can play it in a pc or a dvd player

Thank you.