Vista refuse to boot if the Disk signature (NT Drive Serial Number) has changed. But SBM modifies that four bytes of the MBR (at offsets 0x1B8 to 0x1BB).
So to install SBM and keep the possibility to boot Vista, we need to do the following:
1) save the four bytes value (on paper for example);
2) install SBM;
3) restore the four bytes (and also set the preceding byte (0x1B7) to zero to keep the "SBM Bad!" string ending -- the string does only looze the CR-LF).
I've done that by using PTS Disk Editor on the Ultimate Boot CD, since between step 2 and 3 you cannot boot Vista (and also because SBM is installable from that same CD)
Est-ce que c'est la même chose avec Windows 7 ?