Can't boot from installation USB?

[ChampionnEthan]

Ever since I installed a fresh copy of Windows 8.1, no BIOS update, I can't boot from installation devices.  I set up a USB Drive with a legit Windows 7 Professional ISO and I can't boot from it.  I've tried 3 different ISOs and even changing many settings in UEFI-BIOS.  In BIOS the device shows up as a UEFI bootable device, shouldn't a Windows 7 installation drive be Legacy?  I've done this many times before and this is the first time it hasn't worked and first time it showed up as UEFI.  Even selcting it manually from the boot menu instead of changing boot priority just goes straight to Windows 8.1.  Plz halp

 

Edit:  I'm using Rufus 2.8.886 to create the boot device

[ChampionnEthan]

What file system should I use?  I've tried NTFS and FAT32, NTFS usually works

[Naeaes]

Just use Microsoft's own tool to create the drive. Rufus is fine but tricky to get right. You can always start the installation from the OS. Just run the setup.exe. No need to mess with boot priorities and whatnot. 

Whether you use UEFI or Legacy, will determine what installation you get. If you want your OS to run via UEFI (highly recommended!) run the installer from UEFI. If you want legacy installation (I'd only use it for test bench installations) run the USB as Legacy.

[Cralineleader]

Seconding Naeaes here. Using the installation media is far easier than slapping the ISO on with Rufus. I only really use Rufus for weird ISOs like key crackers.

[PalladianPD]

Windows 7-10 can be set up for BIOS MBR, UEFI MBR or UEFI GPT. If they aren't booting I'm guessing that your authoring them as UEFI but trying to boot as legacy which will not work.

[Sors]

Try to boot from the USB after restarting windows (not shutting down, you have to restart),  I notice that is the only time my laptop lets me load a disc with Ubuntu, and I believe this is a "feature" of windows 8.

[Kryis]

9 hours ago, ChampionnEthan said:

Ever since I installed a fresh copy of Windows 8.1, no BIOS update, I can't boot from installation devices.  I set up a USB Drive with a legit Windows 7 Professional ISO and I can't boot from it.  I've tried 3 different ISOs and even changing many settings in UEFI-BIOS.  In BIOS the device shows up as a UEFI bootable device, shouldn't a Windows 7 installation drive be Legacy?  I've done this many times before and this is the first time it hasn't worked and first time it showed up as UEFI.  Even selcting it manually from the boot menu instead of changing boot priority just goes straight to Windows 8.1.  Plz halp

 

Edit:  I'm using Rufus 2.8.886 to create the boot device

Use the media creation tool, have had issues in enterprise environments using refus for UEFI where WDS,SCCM etc wasn't an option.