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I installed Ubuntu 14.04 to make a dual boot system after a fresh installation of Windows 7 (64-bit, Professional). Windows 7 was installed in UEFI mode on an SSD, after that I shrunk the main partition and booted the Ubuntu boot stick in UEFI as well. Windows at that point worked without any problems.
I was following a guide, but was not aware of the specifics of UEFI, and here is where I believe I went wrong the first time.
While installing Ubuntu I I created a swap space bigger than my RAM on the SSD and a partition for root formatted in ext4. I also created a home partition on an HDD. What the guide I was using at the time did not mention was telling the installer to change the “Device for boot loader installation” to the EFI partition already there. Instead, it remained on /dev/sda.
Installing Ubuntu went off without a hitch, and when I tried to boot there was the list containing Ubuntu and Windows. I then chose Windows, but it would only show a loading bar with "Windows is loading files" and then return to GRUB.
Following additional posts I found, I used boot-repair, which resulted in GRUB showing Windows 3 times, but still not Windows loading. I tried a few things more, but it was hard to find information as most of it seemed to pertain to Legacy mode or Windows 8.
I deleted the partitions, re-formatted the drive again and repeated the process a few times, doing a few things differently, but always returned to the same problem with Windows not booting.
The last time, I installed Ubuntu to the HDD instead, with Windows on the SSD, and Ubuntu again works fine, but Windows won't boot. I ran the Windows repair utilities, ran chkdsk /f, but the only thing that produced any change was the physical memory repair. When I did that, when booting Windows, the Windows 7 welcome screen flashed for a second, but returned to GRUB after that.
Running chkdsk for the first time also showed a few errors on the SSD, but after that it did not show any more. I also ran TestDisk, which showed everything as ok.
At this point I've been at it for two days, and I don't know what to do.