HELP Pioneer 207DBK doesn't erase BD-RE DL

Does any have an idea why my Pioneer 207DBK doesn’t erase a Verbatim 50GB BD-RE DL?
I burned it 3 weeks ago and now I can’t erase it, at that time tested CDBurnerXP and it burned it with a wrong file system, after that I used Nero and it burned it normally.
Today I wanted to erase it and both programs say it isn’t an erasable disk.

Any clue what the problem could be?
I checked if I installed anything between now and then but I can’t see anything suspicious.

Scrap them and use Imgburn, perform a FULL ERASE.

Problem solved, emulation Software(Daemon Tools) had all its emulations on, after turning off they were recognized as what they are.

[QUOTE=chef;2665414]Scrap them and use Imgburn, perform a FULL ERASE.[/QUOTE]
In Imgburn sometimes isn’t enabled erase option, why ?

…because of the media???