Problem about burning DVD-R discs.

I have a PC with XP O/S and pioneer DVD-RW drive. When I burn CD-R/RW or DVD-RW, every thing goes fine but when I burn DVD-R, after burning, my computer does not get access to the disc and shows no disc in the drive after some times of inserting the disc. I tried this DVD-R on another computer with XP having SONY DVD-RW and Samsung DVD-RW drive. It was running on both the computers well but not on mine. I tried to disable the multi session mode but no changes occurred.
One more thing is that ones I burnt a DVD-R using nero, and when I checked it on my computer, it worked. I checked two or three times, all working, but after some days, the computer could not read the same disc, but it was running on the other computer. After it, I made several attempts to burn DVD-R using nero, both by disabling and enabling the multi session mode but all failed in reading. On another day, I again tried to burn the DVD-R using Sonic Record Now. Burning was successful and I could access it on my computer. Now again the condition is as before and I could not access the DVD-R burnt on my computer using either Nero or Sonic.
What could be the reason behind it and its solution?
I will appreciate any help or suggestion.
Thanks.

 

Maybe the batch of media. DVD burning has a lot of compatibility issues.