Hope someone can help. I having problems reformatting some Optodisc DVD-RW media (OPTDI..SCK001....V)

This is not happenning on all discs, just some. After writing to the disc using either Ulead MovieFactory or VOB Instant CD/DVD I am unable to reformat. The following details from the error log are provided below:

An error occured while writing track 1 at position 0.

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Extended information:
Device: Pioneer DVD-RW DVR-105 (D:)
70 00 03 00 00 00 00 0E 00 00 00 00 31 00
2A 00 00 00 00 00 00 00 10 00


I am using a Pioneer DVR-105 with firmaware 1.21

Any help would be appreciated. Or should I just through the discs away

Thanks

Psiman