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Stop 0xED or UNMOUNTABLE_BOOT_VOLUME

The kernel mode I/O subsystem attempted to mount the boot volume and failed. This error might have also occurred to a system upgrading to Windows Vista with high-throughput ATA disks or controllers with incorrect cabling.

Sometimes your system may appear to work properly when restarted.

Resolving the Problem

Before you can fix this problem you need to figure out what caused it. Did you recently install new software or hardware? This will help out a lot when troubleshooting the problem.

  1. If you are using high-throughput ATA disks and controllers capable of a data transfer rate higher than 33.3 megabytes per second, replace the standard 40 pin cable with an 80 pin cable.
  2. Your firmware (BIOS) may allow for higher transfer rates even though you are using the wrong cables. Try slowing down the transfer rate in your firmware.