TI won't allow me to Create a Backup

New user here, so please bear with me. I just want to back up some data onto a DVD-RW or two. Running version 8, build 889. Windows XP Pro SP2. My optical drive is a Plextor PX-712A.
When I try to back up a partition on to a blank DVD-RW, first I receive a message to "please insert the first media". Well, the media is already in the drive. I then reinsert it, and receive this message

"E00040004: Disk is full.
A possible reason may be poor media quality or Volume 1 located on another CD or DVD disc.
Please press Retry to continue with volume 1 or press Cancel to cancel the operation and stop backup."

Pressing Retry gets me that same error message, time and time again. The discs in question are empty. The DVD-RW's tried were one by Memorex, and another by Sony.
Any ideas/suggestions? Thank you

 

Have you tried formatting the media before running TI ?

 

Hello Carbo,

Thank you for choosing Acronis Disk Backup Software.

In order to store the image to DVD you need to preformat DVD disks first as described at our site. Please let us know whether the problem persists after you use preformatted disks.

Thank you.
--
Ilya Toytman