Help with booting windows, and Hard disk/Solid State options

[Hatt]

Is it possible to boot Windows off of a 1 TB external hdd or would a disk be essential?
Also, I have a 64gig solid state with an able to run version of Windows on it (tested via friends computer) BIOS recognizes both the SSD and HDD and I've tried booting from both, and I always get "Reboot and Select proper Boot device or Insert Boot Media in selected Boot device and press a key" (pressing a key does nothing) I'm almost certain this isn't a hardware issue; but you never know. What should I be looking for in my SATA options or booting options for "Compatibility Support Module"?

Anything would help at this point
(this is my first time building a computer)

 

[himnextdoor]

Is it possible to boot Windows off of a 1 TB external hdd or would a disk be essential?
Also, I have a 64gig solid state with an able to run version of Windows on it (tested via friends computer) BIOS recognizes both the SSD and HDD and I've tried booting from both, and I always get "Reboot and Select proper Boot device or Insert Boot Media in selected Boot device and press a key" (pressing a key does nothing) I'm almost certain this isn't a hardware issue; but you never know. What should I be looking for in my SATA options or booting options for "Compatibility Support Module"?

Anything would help at this point
(this is my first time building a computer)

Does the SSD have a partition on it?

 

[Tom Tancredi]

NO. You have to have a INTERNAL HDD or CD to boot from only for WINDOWS (Linux and other OS are different).

Your second issue is because you have 'tried' to install multiple copies of Windows on the same computer but on different drives. ERASE ALL DRIVES and just install to the SSD.