R
Richard Grodecki
This is being posted as an additional answer for a problem that a closed thread helped me solve: Unable to Boot Windows 10 with External Hard Drive Attached
I was having this issue with my laptop, where if the External USB drive (2tb Adata USB3, 1 NTFS partition) was connected on boot, I would get the familiar 'failed to find operating system' greeting just after POST. Most times, when you have a USB drive connected on bootup and the computer fails to find the operating system, it is due to bios boot settings attempting to boot devices out of order, trying your USB device prior to your internal drive. I scoured the settings and this was not the case, but proceeded to disable all USB booting period as a troubleshooting step. Same result. I could start up my Windows 7 laptop with the same USB drive connected without issue (with comparable bios settings) fine, so it appears that it was not the BIOS doing the boot, but the Windows 10 Boot Loader attempting to start the incorrect drive. My system disk on this laptop is a single 1TBm-sata that was setup by windows (100mb system partition[ntfs], ~930GB C: drive[ntfs], 628mb Recovery Partition). Both system HDD and USB HDD are set to MBR, not GPT.
The fix I found was to remove the 'Active' bit that was set on the USB HDD. Since I wasn't booting or intending to boot from this disk on any of my systems, this was an acceptable fix.
Looking at the Boot configuration with BCDEdit, my entries refer to Boot Manager and Boot Loader as "\Device\HarddiskVolume1" and "partition=C:", respectively, instead of a unique ID like GPT would use. Does this mean that regardless of Bios boot order or boot settings of what devices to use, the Windows Boot Loader is victim to the order drives are recognized in the Bios period (and thus the order windows assigns drive letters before it has a chance to read any registry settings later in the boot process)? Is there a way with MBR to preciesly define the boot device in BCDEdit?
Hopefully this helps someone find the less sought after.
Continue reading...
I was having this issue with my laptop, where if the External USB drive (2tb Adata USB3, 1 NTFS partition) was connected on boot, I would get the familiar 'failed to find operating system' greeting just after POST. Most times, when you have a USB drive connected on bootup and the computer fails to find the operating system, it is due to bios boot settings attempting to boot devices out of order, trying your USB device prior to your internal drive. I scoured the settings and this was not the case, but proceeded to disable all USB booting period as a troubleshooting step. Same result. I could start up my Windows 7 laptop with the same USB drive connected without issue (with comparable bios settings) fine, so it appears that it was not the BIOS doing the boot, but the Windows 10 Boot Loader attempting to start the incorrect drive. My system disk on this laptop is a single 1TBm-sata that was setup by windows (100mb system partition[ntfs], ~930GB C: drive[ntfs], 628mb Recovery Partition). Both system HDD and USB HDD are set to MBR, not GPT.
The fix I found was to remove the 'Active' bit that was set on the USB HDD. Since I wasn't booting or intending to boot from this disk on any of my systems, this was an acceptable fix.
Looking at the Boot configuration with BCDEdit, my entries refer to Boot Manager and Boot Loader as "\Device\HarddiskVolume1" and "partition=C:", respectively, instead of a unique ID like GPT would use. Does this mean that regardless of Bios boot order or boot settings of what devices to use, the Windows Boot Loader is victim to the order drives are recognized in the Bios period (and thus the order windows assigns drive letters before it has a chance to read any registry settings later in the boot process)? Is there a way with MBR to preciesly define the boot device in BCDEdit?
Hopefully this helps someone find the less sought after.
Continue reading...