W10 & Yosemite Dual boot

[Hide89]

I've got Yosemite up and running smoothly on an ssd and I also have another ssd from which I boot windows 10. Both boot perfectly but i have to go to the bios to boot windows. When i boot to yosemite I can choose Windows NTFS but then I get the error that the operating system is not found. Is there a way to fix this?

 

[Going Bald]

I've got Yosemite up and running smoothly on an ssd and I also have another ssd from which I boot windows 10. Both boot perfectly but i have to go to the bios to boot windows. When i boot to yosemite I can choose Windows NTFS but then I get the error that the operating system is not found. Is there a way to fix this?

verify if Win10 is installed UEFI or Legacy BIOS mode by running msinfo32

 

[Hide89]

verify if Win10 is installed UEFI or Legacy BIOS mode by running msinfo32

Thanks for the help!
It says Bios mode UEFI.

I also have "EBIOS read error: Error 0x31" when booting to Yosemite. Does this have anything to do with that?

 

[Hide89]

any ideas on how to fix the "the operating system is not found" error when choosing Windows NTFS?

 

[Going Bald]

any ideas on how to fix the "the operating system is not found" error when choosing Windows NTFS?

repair the boot sector or re-install Windows

 

[Hide89]

hmmm i'm not going to reinstall windows How do I repair the boot sector?

 

[Going Bald]

hmmm i'm not going to reinstall windows How do I repair the boot sector?

See https://support.microsoft.com/en-us...the-windows-re-to-troubleshoot-startup-issues