365 product key error

Yes thanks it sorted it

Hi, Marc Fawcett

The key normally needs to be redeemed online once and linked to a Microsoft account. After that, activation is done by signing in, not by entering the key again.

Here are some suggestions you can try:

On either Windows or Mac, open Microsoft 365 setup, sign in with the Microsoft account you want to keep, and enter the 25-character key carefully.

If the message says “This product key has already been used,” do not enter it again. Sign in to your Services & subscriptions page. If Microsoft 365 appears there, select Install, then open Word and sign in with that same account.

If the key is shown as invalid, check commonly confused characters such as B/8, G/6, and O/0. If the error says KEY_NOT_ACTIVATED, the retailer must activate the card at the point of sale.

On Windows, run the Microsoft 365 activation troubleshooter. On Mac, open Word, select Sign in, and use the account linked to the purchase.

If it still fails, contact the retailer with the receipt and exact error message.

Thank you for your patience in reading, I hope this information has been helpful to you. 

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