ok im posting this because you said ASAP..
So heres a quick reply, then il read your post and possibly edit..
Step 1. Buy splinter cell (the 1st splinter cell. not chaos theory or anythiing Just splinter cell.)
step 2, find and download Krazies ndure 1.1.1 Splinter cell exploit. (ntsc or pal, depending on what xbox type you have)
Step 3, transfer the save files to whatever medium your using to transfer them over to the xbox. "action replay/whatever) and use xplorer360 to transfer the files from the pc to the actiopn replay.
Step 4, put the saves on the xbox. (you may have to press right to highlight the actual save to say copy)
And dont have any other splinter cell saves on the xbox.
Step 4.a (if your xbox is not updated to go on xbox live, use halo 2 live enabled game or a live enabled game that was released after halo 2. try to log on to live and it will update your dash board)
step 5, boot splinter cell. Say start game/load/checkpoints
Step 6 follow all the onscreen instructions
Step 7. Download Hexen "heimdalls xbox engineering disk" and burn it to a dvd-r ate 4x or slower.
step 8. boot the xbox with the hexen disk
Step 9. Chose softmod 1 click install, krazies ndure 1.1.1 follow the on screen instructions. install Unleash-x "basic install" dont turn off your xbox untill all steps have been completed. "when you back up your eeprom you will have to back up out of the menu to get to the basic install option"
Step 10, Enjoy your soft moded xbox.
ok read your post.
the xbox unlocks the hard disk for only a short period of time on boot. Error 12 extends that time frame but its not an indefinate ammount of time.
To view your xbox disk contents on the PC. use XPLORER360 in windows.
that will allow you to see the contents of the hard disk provided it is infact unlocked..
"you can also transfer soft modded files to the hard disk at this point if you have them. (do them 1 file at a time, 1 folder at a time)"
I personaly dont like spwaing IDE cables from drives when they are in use, Its a short cut to a dead hard disk.
i dont have any expirience in softmodding a SATA drive via Xboxhdm. in my expirience the hard disk has to be Primary master "the 1st ide device on the 1st ide channel."
in actual fact i only use xboxhdm to upgrade softmodded disks, and if i was hotswaping i always transferd the files voa XPLORER360 then upgraded the mod via hexen..
usb booting..
obviously needs to be set in bios "1st boot device USB" But prehaps the USB device is not formated to be bootable.
Again i have no expirience of usb booting as i simply use xboxhdm 1.9 on a Ide cd "primary slave", and then the hard disk is primary master.
Hope this helps.
P.S
the reason i say get splinter cell is because it dosent matter what version (release version) it is, even the platinum would work.
P.p.s
can people please stop linking to files that contains official/modified bioses and exploited stuff (dash boards/softmods/ETC)
We arent allowed to do that here.