Please make sure you purchased the correct upgrade option according to the program variant(Pro Platinum, Expert, Deluxe or Designer etc) and its version.
The Installation will work this way if you have purchased an upgrade to the latest version from a prior version:
1) First, you will be asked to enter the keys which you received for the latest purchased version. The program will be installed.
2) When you right click the program icon and select "Run as Administrator", you will be asked to enter the serial key of previous version which you owned to activate the latest version.
The program will be activated successfully, if you put they keys in the order mentioned.