I remember seeing a problem on here that the OP had connected his external drive before he booted and ran into problems booting. I accidently connected my my external before it was booted and my boot was messed up. I have since corrected it and do not even know if the two are connected. Would booting with an external drive connected mess up the boot from C: drive? I don't see how it could, but just asking. Thanks,
You're not really booting from the "C" "drive" -- as the BIOS has no concept of drive letters; instead, you're booting from whichever disk is at the beginning of the list of disks connected to your PC, and then, from whatever partition on that disk has the boot flag set.
Connecting an external drive would change the list of drives and it might be such that the external drive is then "first" in the list, and that drive may then become the default boot drive. But, when the drive was removed, and the PC rebooted, on a then single-drive system, booting should default back to the "C" "drive".
If you had a multi-drive system, and the "C drive" was not the first drive (by default) , then connecting an external drive and removing it, could then force the BIOS to default back to the "first" drive, and in this case, the PC would not boot anymore.
@ bigmck
Is this the thread that you mean?
W7, trying to boot off of usb, msi motherboard
I think that somehow, the OP has messed up his MBR, though I don't know how booting from an external drive would do that. I dual boot all of the time, though not from an external.
I wasn't trying to boot off a USB, but I had the external plugged in when booting and the normal C: drive wouldn't boot. I finally fooled with it and things are OK, the external was the only variable that I had. Maybe it was just a weird coincidence. I don't see how the external could have affected the boot, but just thought I would ask. Thanks,
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