DVD-R with 1 GB info but data is missing

[CarlosX]

I burned 1 GB of info in a DVD-R disc. Computer could read it perfectly and said 1 GB was recorded and 3 GB still free available for more data.
Next day I tried to add more data, 0.5 GB in a folder. All was OK, I dragged folder to DVD and PC said it was doing the job, after 2 minutes said folder was ready to be burnt. But the previous folders did not appear. I quit burning and tried to check the information on DVD. right- clicked properties and PC says it has 1 GB of data burnt and 3 GB available. But if I try to read the information I had burnt before, nothing, no files or folders.
May I still recover the 1.0 GB recorded first day? HOw?

 

[ITLogicSystems]

When burning multiple sessions to a DVD-R disk, if the sessions are not left open or closed improperly, then it can "lose" data or make the entire disk worthless. As for recovering data from a DVD-R or any optical disk, for all intents & purposes it's a lost cause, it's not impossible, but it would cost out the wazoo and the likelihood of recovery is slim.
As cheap as DVD-R disks are, don't burn multiple sessions, just burn once and be done with it.

Hope this helps, take care!