Migrating installed windows -> USB Flash

Posted on 2009-02-14
Last Modified: 2012-05-06
Right now I have Windows installed and working fine on OCZ Throttle 8Gb drive in SATA2 mode.

When I try to boot windows from this drive in USB mode it obviously BSODs with 0000007B error (boot device inaccessible). Is there any way to fix drivers in the installed system so that it will boot in USB mode too?

I know that I can install BartPE or other PE based systems, but I want "regular" Windows XP, probably with some kind of USB drivers from BartPE or something.

I guess the fact that I can boot into this system in SATA mode and change any registry/driver setting should make the task a little easier.

Any ideas?

PS. OCZ Throttle - you may connect it to eSATA from the one side, and to USB2 from the other, that's how it works ;-)
Question by:BarsMonster
    LVL 31

    Accepted Solution

    I have successfully installed windows on a USB external hard drive using this guide:

    The main issue is that USB devices are by default not made available as Boot Bus Extenders. The USB drive is not available early enough in the bootup process to be booted from to load windows. You modify several INF files and repack them into the I386 folder to make the relevant SYS files load earlier in the bootup process.

    So, to make your existing installation not BSOD, you need to get those usb devices in the above guide to load earlier in the bootup process. I'm not sure how the changes to the files in I386 will translate into a change to the actual windows installation, but there's a good chance it's fairly straight forward.
    LVL 5

    Author Comment

    That's a good start, I did these modifications and tried to update USB drivers for all USB devices... Still see 7B
    LVL 31

    Expert Comment

    Well, these instructions are for creating a new windows install CD for installing a fresh version of XP. It doesn't directly apply to your existing installation. Perhaps you can do the changes in the above guide, reburn a new ISO of a windows xp setup disc with the changes made, and then do a repair installation overtop of your existing installation?

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