DVD backups won't play

Hi Clever People,
I have been using 1 Click DVD (at your suggestion) for some time now to back up DVds. I recently upgraded to Pro version. I have been transferring my dvds to hard drive for travelling and now 1 Click DVD Pro won’r play any back up versions on my Toshiba Laptop (where they were all created)
I have cleaned the lens and still nothing. It will not even recognise them.
I use Verbatim DVD -R discs and have done for some time. This problem has only started since I added a new 2TB external hard drive to record the dvd’s. They still work fine on my main computer.
Hope someone can help!!