Dear Sirs, We have a CADian 2012 Professional purchased in Febr.2013 and have used it until now without problems. Serial number is: I14 4122 75XKPP02 Now we had to change to computer, and have installed CADian on the new computer from the CD, and could not re-register the product. Please reset our serial number in order to can register our CADian to use it on the new computer. Please send us a short reply when we can register. Thank You in advance, Best regards, Alexandru Seica, VIVA COM SRL, Targu Mures.