Open CCC and Check Registration Status
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Click on the Carbon Copy Cloner menu. If you see a Show Registration... menu, then CCC is already registered on your Mac. You can select Show Registration... to view the registration details. If CCC is not yet registered, you will see a window that opens on launch indicating that CCC is currently running on a trial basis. If you already dismissed that window, you can choose Purchase CCC... from the Carbon Copy Cloner menu to reopen the Trial window.
Unregistered CCC
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If CCC is unregistered, you will see the Welcome to Carbon Copy Cloner registration screen. If you have previously purchased CCC, click on I already have a license.
Copy and Paste in Registration Codes
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Copy and paste in the name, email address and license key exactly from your registration email. Note: If you try to use a different name or email address, the license key will show as invalid. Click Register.
Properly Entered Code
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For your reference, here is what a registration code should look like. Note that the registration code automatically breaks between the two lines; do not use the Return key when entering your registration code.
Successfully Registered
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Once your copy of CCC is successfully registered, you should see a "Thanks for registering!" screen.