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Hi All, I have been trying to install OS(1903) in Hyper-V VM But it keep failing at Apply Operating System. But the error says as below. ![30888-image.png][1] [1]: /api/attachments/30888-image.png?platform=QnA
Hi @Simon Ren-MSFT , Thanks for your time in assisting this issue. This issue has been resolved by changing Gen 1 to Gen 2 Drive of Hyper-V Vm.
Hi,
Thank you for coming Microsoft MECM Q&A forum.
==>"Failed to make volume C:\ bootable. Please ensure that you have set an active partition on the boot disk before installing the operating system."
When in BIOS mode, you can only install the OS to a BIOS partition scheme. If you want to install the OS as a UEFI scheme, you need to boot to UEFI. This is because the task sequence will only create boot systems that match the current mode.
Please help check your format and partition task and make sure that you've set the proper partition as active. Copy a default format and partition task from a Wizard generated task sequence if you need to.
Thanks for your time.
Best regards,
Simon
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Hi @Simon Ren-MSFT ,
Thank you so much for your time in help on this. I have created a Native TS from CM Console without using MDT and another one with MDT as well but both leads to same issue. More importantly i didn't make any changes after i created them.
Hi,
Thanks for your reply.
May we know which type you are setting in the BIOS, UEFI Mode or legacy BIOS mode? Does the partition format in task sequence match the setting in BIOS? If possible, please share the BIOS screenshot and task sequence screenshot.
For more information, please refer to: Boot to UEFI Mode or legacy BIOS mode
Thanks for your time.
Best regards,
Simon
If the response is helpful, please click "Accept Answer" and upvote it.
Hi,
Thank you very much all your reply and sharing. We're glad that the question is solved now. It may help others who have similar issue. Here's a short summary for the problem.
Problem/Symptom:
Failed to install OS(1903) in Hyper-V VM with the error "Unable to make C: Bootable"
Solution/Reason:
Change Gen 1 to Gen 2 Drive of Hyper-V VM.
Best regards,
Simon
If the response is helpful, please click "Accept Answer" and upvote it.
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.