EFI system partition on wrong drive

coinup · 04 Feb 2015

How do I get the efi partition on the c:\ drive????

**cluberti** · 04 Feb 2015

First, volume letters != drive letters. Unless you pre-partition and image yourself, Windows setup will place the EFI partition on the first physical disk presented to setup by the EFI OS, even if it's not actually the first disk installed into the system. I used to get this all the time with an older Asus board, where my (larger) storage volume would get the EFI partition, even though I chose a different physical disk to place the installation volume on. I ended up backing up my data and moving the SATA cables around until it was the way I wanted it (and no, it didn't match the port layout on the motherboard unless I set the Intel ICH configuration from "RAID" to "AHCI".

gregrocker · 04 Feb 2015

This is why all other drives should always be unplugged during any Install or Startup Repair.

To put all of these necessary UEFI partitions on the same drive I would install flexible Macrium Imaging - Windows 7 Help Forums to C and have it save a backup image of the partitions required to boot including EFI System Partition, possible hidden MSR partition, and C. Do not include any of the other partitions in the image.

Then boot the Macrium boot disk you've created to Recover from the image, drag the necessary partitions to the target drive after deleting C using the link on the Recovery page. It should automatically adjust C size but you can manually adjust that using the link it creates under the partition once dragged to the target drive.

Now boot into BIOS setup and set the Win7 drive to boot first instead of the old EFI System drive, Save and Exit to boot Win7.

If for any reason Win7 won't boot, unplug all other drives to boot into the Win7 disk or System Repair Disk to run Startup Repair. Afterwards I would plug Disk0 cable into the Win7 drive so it is in first position where future repairs cannot derail the System partition again.

In the unlikely event this fails, you'll still have the old EFI System partition on the other drive to boot the C image by setting it first to boot in BIOS. Don't let it get set first to boot again otherwise.

Finally, none of those other drive partitions should be marked Active which is only used to flag a drive intended to boot an OS on an MBR disk, so mark them Inactive if they are not there for that purpose alone: Partition - Mark as Inactive - Windows 7 Forums