Question Main drive not recognized by system when booting ?

okrobie

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Mar 2, 2016
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Hello all,
My PC wont boot all of a sudden. and if I boot with a Win-PE USB stick the drive is not seen in explorer, but if I run a utility like AOMEI Partition Assistant Pro, (naturally I have to switch the BIOS to legacy to do that) the drive is there and looks normal. Out of desparation I tried switching from GPT to MBR and back and it seems to run normally, but if I switch back to Boot Manager and UEFI it still won't boot, or even be recognized. What can I do now? I'm sure it's just a matter of rebuilding the boot block, but I don't know how to do that. Thanks for any and all help.