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''Missing operating system'' can't boot after trying to convert bios from legacy to uefi, help RRS feed

  • Question

  • Hey guys, I already tried to post this question on another forum, they tried but then they send me here and maybe you can do something for my problem.

    Here is the original thread, https://answers.microsoft.com/en-us/windows/forum/windows_10-performance-winpc/missing-operating-system-cant-boot-after-trying-to/f6a82a4c-533f-4447-af4e-94162c78e45d?messageId=f8ab0de2-f35d-4648-9ba2-fe5bc6bdbb3a

    My last question is from yesterday but I still want to try asking you too just to save time eventually.. so in the last one I put interesting info cause I can boot in the windows installation section AND open cmd.

    Friday, October 20, 2017 6:04 PM

All replies

  • Welcome to TechNet; it sounds like you learned a valuable lesson!

    Never configure your production environment without first testing your changes in a sandbox environment.

    Legacy to UEFI is not apples and oranges; it's more like apples and seething rabid toddlers trying to claw your eyes out.

    also; by the sounds of it you have wiped your drive a few times just to get it working?

    so, if you are expecting for it to magically revert to before you started this clown fiesta. More than likely out of the question.

    if you want to just get a WORKING INSTALLATION of windows. Which will remove all other O/S's or Boot Loaders you have on the machine. (ALL CURRENT DATA WILL BE LOST)

    Hard delete all partitions; create a single partition formatted NTFS. 

    Point installer to the new single partition keep hitting next. 

    Congrats you are now a IT professional.

    Friday, October 20, 2017 6:30 PM
  • I don't know what idea you got of me but I'm nothing more than a 16yo that just thought going from legacy to uefi was as easy as uefi to legacy, and I don't even know what I did wrong, I just get told that I did a terrible mess like it was someone else's pc..

    Now what do I have to do exactly? How do I create a single partition formatted ntfs? Do I need to use cmd? Will this fix my pc trying to boot from lan and failing? And can I please get my bios to uefi again...?

    Friday, October 20, 2017 7:29 PM
  • run through the installer you were showing pictures of. select drive 0 partition 1 and under that section it should give you a list of options. one should be delete partition. repeat for all partitions. under the section there should be an option to refresh. it should see 'unpartitioned space' select create partition in the bottom left. use as much drive space as you can be sure to make sure it is set for NTFS ' it will be a dropdown option ' once the partition is created select the new single partition and continue with the install.
    Friday, October 20, 2017 7:50 PM
  • Oh so I just needed to do a clean install, and I see that my pc won't fail to boot from lan anymore.

    So it feels really good to be back, but now I'm kinda at the starting point, and so now that my biggest problem is solved do I have to ask somewhere else how to move my bios from legacy to uefi or?

    Friday, October 20, 2017 10:38 PM