From experience, setting up an SSD boot on a Pi requires a little bit of art. I do the following, but there may be better ways.
a) I use Linux and GParted to format the whole drive as Fat32. Windows will not let you do this without using the command line.
b) I then use Win32DiskImager.exe to burn the .img file onto the SSD
c) I then boot the Pi3B with the SSD installed. If a Pi3B is used it just works. For a Pi3 the mobo needs initialising first link
d) Allow it to boot twice as it does something with the boot partition.
e) After the second boot, change the Pi password and expand the partition. It will say it does not know how to do it, but ignore the warning as it ‘probably’ sets a flag.
d) I then shutdown, remove the SSD and use gparted to expand the Home Pi partition,
e) Reinstall the SSD then use as normal.
I’m not sure if all these steps are required but when I follow them it works whereas I’ve had failures when trying shortcuts. I recommend using the ‘official’ power adapter as I’ve had problems with Chibay ones.
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