Right click CMD.EXE and select Run as Administrator,
Type CD\ to jump into the root directory,
Change to the DVD drive with the Blu-Ray disk installed, type LABEL and
hit enter to see if it will let you name the Volume.
If it works, type DIR to see the new LABEL and what is installed on it.

Hello Badger, thanks for your help.
This is what I got with the CMD:

Microsoft Windows [Version 6.0.6002]
Copyright (c) 2006 Microsoft Corporation. All rights reserved.
C:\Users\Grendicd\
C:\f:
Data error (cyclic redundancy check).

In Windows Explorer, the bluray drive is shown as a disc icon with "BD-RE"
on it. When I click on this icon to see the content of the BD-RE, Windows
asks me if I want to format the disc, I answer yes , type in the volume
label, and as before , I get the message "Windows was unable to complete the
format".
I'm wondering if the problem comes from this brand of BD-RE (LG) or is it
generally a problem with BD-RE formatting in Vista SP2?

See you,

Gz