Strange Issue Dual Booting Windows 10 and Sierra on Two Separate SSD's

[Bionic Beast]

I used to have El Capitan and Windows 8 working on two separate drives perfectly for the most part and have had dual boot working great for years. For some reason after some time I started having strange issues while booting into either OS or having slow loadup speeds when booting onto mac side. So I decided while I had some free time I was going to do a full clean wipe of both the windows and mac ssd and start fresh. To summarize my installation process. Made a windows 10 (rufus GPT) and sierra usb install on two usb drives. Booted into sierra installer, wiped both ssd's with disk utility as Mac os Journaled and GUID, and then installed sierra. I get sierra working fine using Clover UEFI bootloader and I can boot from it without the need for the usb installer (aka clover is working fine) so I begin the windows install. I unplug all drives except the windows ssd and install windows onto that. I make sure I can boot into windows with no issues as well. Now here is where the problem occurs. I plug my drives back in, and my 3tb storage hdd is recognized just fine in windows and clover, however in clover I am not longer able to see my sierra ssd, but I can see the recovery partition for it. So I use the sierra install usb and check in disk utility and it seems like somehow after the windows install, my Sierra partition is being corrupted/wiped because under the ssd name the partition no longer says "Macintosh HD" but is being replaced with just "--" So somehow after the Windows install, the Sierra partition which is on a completely different ssd is being wiped out. I have tried this process 3+ times and the same thing keeps happening. I know I am not wiping the partition because the ssd is unplugged during the windows install. Only when I plug it back in and then try t boot from it or the sierra install usb do I realize that the partition is gone. So I am not sure what in the world could cause this but any input or ideas would be super appreciated because this has already taken up close to 24 hours of time spread across a few days trying to resolve and I am out of ideas and extremely stress because of this. Thank you!

Relevant Specs:
MoBo: GIGABYTE GA-Z87X-UD4H on version F9
Two Samsung 840 EVO SSD's


UPDATE:

Plot twist...

So since I already had windows installed and my sierra partition got removed somehow, I decided to just keep windows on their and install sierra afterwards. Once I did that, the same thing that was happening to sierra was happening to windows. And I cant boot to it via clover or any other method. So i checked and the only difference is the partition name still showed up in Disk Utility but it said that only 300mb of it was being used (it should be gigs of data since the OS was installed on it). So now Sierra works great but windows is borked. For some reason whenever I install one os, the other is getting destroyed and I have absolutely no idea why.

[ximochimo]

I there,

 

I have the same trouble, but with Mavericks and windows 10.... Any idea?

 

Thanks

[emma34]

On 12/26/2016 at 1:43 AM, Bionic Beast said:

I used to have El Capitan and Windows 8 working on two separate drives perfectly for the most part and have had dual boot working great for years. For some reason after some time I started having strange issues while booting into either OS or having slow loadup speeds when booting onto mac side. So I decided while I had some free time I was going to do a full clean wipe of both the windows and mac ssd and start fresh. To summarize my installation process. Made a windows 10 (rufus GPT) and sierra usb install on two usb drives. Booted into sierra installer, wiped both ssd's with disk utility as Mac os Journaled and GUID, and then installed sierra. I get sierra working fine using Clover UEFI bootloader and I can boot from it without the need for the usb installer (aka clover is working fine) so I begin the windows install. I unplug all drives except the windows ssd and install windows onto that. I make sure I can boot into windows with no issues as well. Now here is where the problem occurs. I plug my drives back in, and my 3tb storage hdd is recognized just fine in windows and clover, however in clover I am not longer able to see my sierra ssd, but I can see the recovery partition for it. So I use the sierra install usb and check in disk utility and it seems like somehow after the windows install, my Sierra partition is being corrupted/wiped because under the ssd name the partition no longer says "Macintosh HD" but is being replaced with just "--" So somehow after the Windows install, the Sierra partition which is on a completely different ssd is being wiped out. I have tried this process 3+ times and the same thing keeps happening. I know I am not wiping the partition because the ssd is unplugged during the windows install forpcworld. Only when I plug it back in and then try t boot from it or the sierra install usb do I realize that the partition is gone. So I am not sure what in the world could cause this but any input or ideas would be super appreciated because this has already taken up close to 24 hours of time spread across a few days trying to resolve and I am out of ideas and extremely stress because of this. Thank you!

Relevant Specs:
MoBo: GIGABYTE GA-Z87X-UD4H on version F9
Two Samsung 840 EVO SSD's


UPDATE:

Plot twist...

So since I already had windows installed and my sierra partition got removed somehow, I decided to just keep windows on their and install sierra afterwards. Once I did that, the same thing that was happening to sierra was happening to windows. And I cant boot to it via clover or any other method. So i checked and the only difference is the partition name still showed up in Disk Utility but it said that only 300mb of it was being used (it should be gigs of data since the OS was installed on it). So now Sierra works great but windows is borked. For some reason whenever I install one os, the other is getting destroyed and I have absolutely no idea why.

Hi, I am having the same issue, did you happen to resolve it?

 

Thanks

 

Emma Watson