Can't playback ConvertXtoDVD file on computer

The file build by ConvetXtoDVD plays just fine on DVD player but won’t play on the computer. I’ve tried it on two different computers. I want to be able to play the DVD on a laptop as well on DVD player. What am I doing wrong?

Did you finalized the burnt disc?.

Thanks TCAS for the help – the file did finalize. I found that the problem was that when I put the DVD in the computer to play I clicked on the file name to activate play. What I needed to do was click on a little red box just in front of the name. The DVDs are fine and play on the computer – it was just an operator error. Feel like such a dummy.
Thanks again.