product key is incorrect

Hi there, THU. There are two ways to verify the correct product key location. I will provide further explanation below.

If you purchased the product from a retailer, you can find the product key and license number printed on the packaging or included in the product box. On the other hand, if you made the purchase directly through Intuit, the license details, including the product key, are sent to you via email. Ensure to check your inbox, including spam or junk folders, for the email containing this information.

Since you've mentioned that the product key is incorrect, we suggest reaching out to our Customer Phone support team. They can help verify your purchase details and provide the correct product key to ensure activation. 

To contact, here's how:

1. Click on this link: https://quickbooks.intuit.com/learn-support/en-ca.
2. Scroll down to find and select Contact Us.
3. From the screen, you'll be prompted with What can we help you with? section.
4. Choose your product, then follow the on-screen steps.

Let us know if you have further questions and concerns. We are here to help.

@THU HA 

Which QB Desktop year version? There is a good chance that you were not using the correct installer file.