RKT65L-8YRUW-U5L1G-1UKIITWGY-0GY1P-7DLGU-N46DU-Q6O0KSJOI-RDQ9N-TGIR5-R4IJGMO. The PDF-XChange licensing system offers both the standard serial key method of licensing applications as well as the option of using a license file. Registration Code. If you need Registration