Have you gone into Windows to "set" the drive letter of your USB drive?
Do you ever unplug/replug that USB drive?
If I don't unplug the USB drive the computer tries to boot from the drive. I've unplugged/replugged many times without it "forgetting" where it is, but then there have been these two occasions where it hasn't worked. Could it be that plugging the USB drive into other computers, then bringing it back to the video editing computer, is causing problems?
I haven't "set" the drive letter, but I'm always careful to use the same USB slot. How would I go about "setting" the USB drive?
Thanks for your help.
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As for trying to boot from the USB drive, you need to go into your BIOS and change the boot order, so booting from the internal hard drive is before the USB in the boot order
Thanks for your advice John.