Illegitimate Key

If it is Office, you have seen it again cracked, or used KMS key, ... not yet. Once you have used those activation methods before you enter the key, when you take IID, I will be IID not of the key you just entered. Please remove the invalid key before entering the new key!

The key check gives error code 0xC004C008 

Hi friend!
For this case, Microsoft may detected the key which you are using is illegitimate product then they blocked and don’t give us the confirmation ID.

you need check key first