[mpoole226]

Well going to "Remove Programs" and deleting Coreplayer then going to "File Explorer" opening "Application Data" and deleting the Coreplayer folder will fully uninstall Coreplayer. You can then reinstall it and it will ask for the serial #. Using the serial number given here will allow you to get into Coreplayer and use it for a short time. It seems to stop working as soon as you use it to access the internet for YouTube or anything that requires an internet connection. The serial must get validated online and it seems that this one has been flagged and no longer works. So this fixes the inability to put a different serial in, but can't fix the fact that you will get locked out of Coreplayer as soon as you go online with it.