Some pictures would be helpful.
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if you touched your Bios you might want to reverse it to its default state.[br]
in case you haven't done anything to your bios - It might mean that your Os installation is faulty or that your drive is... [br]
in that case, you might want to download a thumb drive version of Windows (if you are on Windows) to repair your installation.
You could also remove your add out try to clean the pin with some dry cloths - try to find some oxidation marks... it can also be a missing contact of the pin on your SSD.
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