Can't Reinstall Norton Antivirus Gaming Edition

I installed a free version of Norton AV Gaming Edition about two weeks ago...

 

But I accidentally uninstalled it,and uninstall requires system reboot. (I didn't notice it was uninstallation, since I was very tired, so I just kept clicking and clicking. I only realized when my system rebooted)

 

But after the reboot I can't reinstall it using the setup, because it says "Uninstall Norton AV Gaming Ed. 2009"

 

But I already uninstalled it. So can you help me reinstall the antivirus?