disappearing bcdedit.exe window

William

I've followed your very well-written process on how to set up a dual boot XP/Vista (vista first) system. The problem is in step 4., Edit boot.ini. When I right click on bcdedit.exe and select Run as Admin, the black dos window fly’s in and out in a flash. It pops up but disappears immediately. What do I do now?
Thanks!
DLS1031