Try closing Impulse and running the following file:
http://sd.stardock.com/curthendzell/fix_registrations.reg
Make sure to follow the link in Internet Explorer, as other web browsers will not handle the file type correctly. Once you follow the link, save the file and double click it to apply it. Then relaunch Impulse. You will need to re-login with your username/e-mail (either will work) and password.
If that doesn't work then please email support@stardock.com and start a trouble ticket. It is the weekend and you may need to wait until Monday for a reply. You will receive an automated ticket number after you email support.