Office 0xC004C003: Microsoft has blocked this product key permanently
Error 0xC004C003 means Microsoft blocked the Office key, usually a resold or grey-market licence. Here is why it happens and what actually fixes it.
0xC004C003: The Activation Server Has Blocked This Product Key
0xC004C003 means the activation server has blocked this product key. Here is how to confirm it, what 0x803FA067 actually means, and what to do next.