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Doh! Stupid me accidentally formatted what I believe was the EFI partition. I had to format the partition again as FAT32 before it would let me reinstall Windows 7. The problem now is that my dual boot for Windows 10 is no longer listed at boot up. The partition is healthy and the drive letter D shows up under My Computer and all the data is still there.  I was hoping this software would help with this.

I tried rebuilding the EFI system partition by selecting the Windows 10 (second partition) instead of the Windows 7 because I don't have the media for that. But it gave "Failed to run system API. (0x0780001500DF0000)"

Attached is the user.log.

Any help or ideas how to restore the second OS option is greatly appreciated! Thank you!
(03-17-2017, 08:09 PM)kuraki Wrote: [ -> ]Doh! Stupid me accidentally formatted what I believe was the EFI partition. I had to format the partition again as FAT32 before it would let me reinstall Windows 7. The problem now is that my dual boot for Windows 10 is no longer listed at boot up. The partition is healthy and the drive letter D shows up under My Computer and all the data is still there.  I was hoping this software would help with this.

I tried rebuilding the EFI system partition by selecting the Windows 10 (second partition) instead of the Windows 7 because I don't have the media for that. But it gave "Failed to run system API. (0x0780001500DF0000)"

Attached is the user.log.

Any help or ideas how to restore the second OS option is greatly appreciated! Thank you!

In your case, you need to try bcdboot.exe to set up multi-boot Windows. Please do the following steps:

1. Run cmd.exe as a administrator.
2. Run "Bcdboot.exe P:\Windows /d /addlast".

The path in red is to the Windows folder of your Windows 10 installation. 

More on the bcdboot command:
https://technet.microsoft.com/en-us/library/hh824874.aspx