Under Windows Vista you should run as administrator to make use of 
it (press the right mouse button while selecting bed, cmd, powershell 
or rxvt to see a menu with this option). 
Under Windows Vista you are even then not allowed to write to the disk
everywhere, unless you make Vista believe there is no file system on 
the disk (http://support.microsoft.com/kb/942448). After erasing the 
content of a disk with killdisk (http://www.killdisk.com/downloadfree.htm), 
it is possible to write to all sectors of the disk. So you can best boot 
Linux from an USB stick or DVD and run the Linux version of bed.
Before making any changes you should ensure that the program is 
working properly. Small changes in the installation can break the 
program. For example an older or newer cygwin1.dll library in you path 
can have catastrophic consequences. Or when you compile bed yourself 
it is possible that ./configure switches on some totally untested 
combination of options because of some idiosyncratic combinations of 
programs and libraries on you hard disk. So copy what you want to 
change to a USB stick and try to change it there before making the 
file system unreadable. If possible, make first a backup of the 
disk you want to change. 
Under windows 95 bed determines size by an ad hoc heuristic. If the 
size seems to be wrong, try to determine it and specify it with the -d 
option at startup. Under windows 95 the size is saved at register key 
HKEY_LOCAL_MACHINE\SOFTWARE\Bed\harddrives.
