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I just purchased a "HP Pavilion 15-B055ca (C7C80UA#ABL) Ultrabook" from my local computer store the other day, as well as an SSD hard drive.

I removed the original 500GB HDD, installed a 120GB SSD, loaded an Ubuntu live CD via USB and used "GParted" to first shrink the windows partitions on the 500GB HDD and then copy them onto my SSD, leaving some space to dual boot Ubuntu 12.10 later on...

I had to re-flag my windows partition to "boot", and I wasn't able to copy over a small partition with the drive formatted to "msft" I believe (probably a proprietary Microsoft formatting that GParted couldn't deal with?), as well as enable legacy mode on my UEFI capable motherboard, but I was finally able to run my pre-installed version of Windows 8 on an SSD, after copying it from the HDD originally provided by HP. I felt pretty good about myself after that! It's an appreciably noticeable difference, that's for sure.

I now wish to disable legacy mode and re-enable secure boot, but whenever I do either of those two things I am told that "Selected boot image could not authenticate" by the UEFI Secure Boot app I presume. Which is odd to me, since I am technically using the exact same windows image installed on the computer when it was manufactured, I have only changed the drive type, size, and removed a small msft formatted partition because I couldn't copy it.

My question is: How do I re-sign my Windows boot loaders and/or re-enable Secure Boot on my laptop and be able to boot into Windows 8?

Thank you for reading.

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Are the original and new drives both formatted as GPT or MBR? – Karan Mar 19 '13 at 4:43
Not sure, any idea how I would check that? The SSD was created and copied to using GParted, whilst the HDD was an original Windows factory install. I would assume that linux creates drives differently than windows. Either way, it doesn't matter, as I tried copying the drive using dd originally to no avail. So I must be able to re-enable Secure Boot using this installation because it's the only one that works using SSD without any installation media available for Windows Standard yet (to me at least). Sorry for the novel... – darkAsPitch Mar 19 '13 at 5:25
In GParted I believe you can select View / Device Information to see the partition table type. As the GPT FAQ states, Windows can't boot in UEFI mode from an MBR disk. – Karan Mar 19 '13 at 5:53
I was able to view the GUID for various drives using GParted in my LiveCD so I assume the SSD is GPT, could the solution be as simple as copying and pasting the GUID from my HDD boot partition to my SSD boot partition using GParted? Is the GUID all that Secure Boot is looking for? – darkAsPitch Mar 19 '13 at 6:34
I suggest you follow Rod's advice below and post the report so the exact details of your current setup are clear. – Karan Mar 19 '13 at 17:46

You can't re-sign anything with Microsoft's key -- only Microsoft can do that. Unless you've modified the boot loader binary, it's still signed with Microsoft's key. Thus, the message you're seeing about a failure to authenticate a binary probably applies to some other EFI binary -- perhaps an EFI version of GRUB. It's really hard to tell what's going on from your description, though; there are just too many technical details you haven't specified. Thus, I recommend you download and run the Boot Info Script, which collects these details in a file called RESULTS.txt. Post a link to that file here.

Chances are you can get this working, but you may need to do an MBR-to-GPT conversion and/or use a tool like Linux's efibootmgr or the bcfg command available in an EFI version 2 shell to re-enable the Windows boot loader. You may also need to install shim or PreBootloader if you want to boot Linux with Secure Boot active. I'm not providing details yet because those depend on your current configuration, which I won't know until I see that RESULTS.txt file.

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