USB boot Problems

[samarsingla]

I made a bootable USB drive using Universal USB Installer on Windows 7. When I try to boot from it, my computer never detects it, however it did detect the USB DVD drive.
How can I check if the USB drive is actually bootable?
Cheers
Samar

[VH-BIL]

Check your BIOS to see if you can boot from it first.

[kalistona]

see proprieties, if dos is marked it is right, anyway few doubt that it is not !
on oem sometimes, another system even in usb, is refused.
take your usb and check for errors, best is defrag and clean ypur windows7 (update i hope), after few try it is accepted without problem.
i suppose your usb key does not need special firmware like securit and it is not all crypted ?

[darkod]

Try to boot another computer with it.

[C.S.Cameron]

In BIOS try to set it as the first hard dive.

[mrwaterdancer]

My WinXP on an external drive works, but not Ubuntu. I tried selecting /dev/sdb during installation but this thing just fails miserably.