>>Each time when remove the program and install again, it comes with a different serial number
Not correct, the serial number is your windows Hard drive serial number, so this is fixed for each computer or laptop or hard drive, this means.
I see you already registered with a serial number D03EF434.
If you have a firewall enabled, disable it, if you have antivirus or any type of adware software, disable it until you register,
I unregired you again, if this did not work, unregister and send me by email your offline serial number.