“NoteBook Says My License is Invalid?”
 
If you see the message



NoteBook is having trouble finding a valid license file.  Why might a license file become invalid?  When you enter a license key, NoteBook saves it in a file in ~/Library/Application Support/NoteBook/Licenses.  At launch time, NoteBook reads your license information from this file instead of asking you for it.
 
A license file is unique and becomes invalid when copied.  If you ever restore your home folder from a backup, for example, NoteBook will not accept the restored license file.  Re-entering your original license key allows NoteBook to generate a new and valid license file.
 
In the panel above, click “Review Licenses” to view your licenses in the License Manager.


Click “Delete” to delete the invalid license file, then “Add” to re-enter your license key.

Be sure to enter your license key and not your license key’s serial number.  NoteBook won’t accept the serial number in lieu of the license key.