You receive the serial number depending on the type of purchase:
- From Adobe website: When you purchase Photoshop Elements, you receive the serial number in an email from Adobe. Look for the subject line "Your Serial Number" or "Your Serial Numbers" in your mailbox.
- DVD: You can locate the serial number on the back of the DVD case. If you have an envelope for your software, the serial number can be on the envelope instead.
If neither of those things apply I would suggest asking the Ebay user you bought it from.
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Noel Bürgler | Adobe Community – Helping InDesign-Users | MacBook Pro 15", macOS Big Sur 11.2 Beta, InDesign 16.0.2
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