: Inside the app, navigate to Help > Activate (or "Register"). You will be prompted to enter your serial number. If you only see "Sign In," you likely have a subscription-based version installed and may need the specific installer for perpetual licenses. Troubleshooting Common "Loops"
If you purchased a subscription for Acrobat Pro or Standard, your license is tied directly to your (email address). No serial number is required. Launch Acrobat DC on your computer. Go to the Help menu and select Sign In . activate adobe acrobat dc