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Recently purchased a new Windows 8 PC.

It came with one hard drive.

I want to a second hard drive to it. This second hard drive is my data hard drive from my previous computer.

However, I have run into issues when the system accesses it.

The drive is found in the BIOS. But is not seen by Explorer or Disk Management.

I have added the drive to the next available SATA slot: SATA 2.

The machine is a UEFI/ACHI based machine.

In my reading I have found people documenting the following:

1) adding multiple partitioned hard drives (like mine is) to UEFI based machines is not possible 2) I have seen it suggested that you can only add blank hard drives to UEFI based machines. However, in doing so, I did not have success. I tried to add it as a hard drive with unallocated space and then as a hard drive with a single simple partition. Both attempts failed.

My ultimate question:

What is the proper procedure for adding a second hard drive to a UEFI/ACHI machine?

I do not want to reinstall the OS and start from scratch as I have seen suggested elsewhere. There has to be a way to accomplish this without all that hassle.

Thanks in advance for your help.

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Windows 8, when installed using the UEFI configuration, will not boot with another drive connected to the system that has an Extended/Logical partition.

This even includes external drives

Credit goes to

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Check in Device Manager to see if it is displayed there. If it is not you may want to look at the drive and see if it has jumpers that are set incorrectly. If it is displayed, see if it has problems or is disabled by default. If it is not OK in Device Manager it won't appear in Disk Management in my experience.

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it is a SATA drive and does not have jumpers. I will have to double check Device Manager. – pflyer Nov 30 '12 at 22:14

Ok, let me tell you the results of my saga with this issue. I DID get my machine to recognize the drive, that is the good news. The bad news: not sure I can tell you WHICH item along the way fixed the problem. I know I know, I should only test one thing at a time. But when you are in the pit of frustration, you just begin to do everything at once with the hope that something will work...

I had read on Win 7 forums about various problems with UEFI and 2nd hard drives. (I know we are dealing with Win 8 here, but so little has been written in the forums as of yet). One astute poster mentioned that adding a drive with multiple partitions might prove to be difficult or impossible.

So here is what I did.

Since I could get the machine to recognize the HDD into the SATA 1 slot (this of course left me without my ODD...). I moved ALL the data from this 2nd HDD to the 1st HDD.

Then, I deleted ALL the partition (three) that I had on the 2nd HDD.

*I unallocated the entire drive. I put the ODD back to SATA 1 and put the 2nd HDD into SATA 2. Not recognized.

*I switched the 2nd HDD back to SATA 1. I created a single partition on the hard drive.

*Again I put the ODD back to SATA 1 and put the 2nd HDD into SATA 2. Not recognized.

*This time however, I went to Device Manager and did a refresh on the Domain Controller and the Hard Drive items. Again, still not recognized.

*I gave up. I left the 2nd HDD plugged into the SATA 2 slot.

*A full 24 hours later, I was on my machine, I just happened to open up Windows Explorer and what do you think I found???? It was now recognizing that 2nd Hard Drive in the SATA 2 as WELL as recognizing the ODD in SATA 1.

So what made the difference? Multiple re-boots along the way from when I gave up and when it was finally recognized? But combined with the hard drive re-partitioning? Did the Device Manager refresh has ANYTHING to do with it? Does time heal all??

I cannot tell you for sure. Weird. Wacky. Wonderful only in that I now have a functioning 2nd HDD without losing access to any other attached drive. Not wonderful, in that, I had to move everything off and wipe it clean.

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What exactly is ODD This answer needs to be cleaned up. – Ramhound Dec 3 '12 at 16:50

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