Where do you activate it?
As explained on the manual and on your purchase receipt, you activate it using the "Register Serial" button in the Addon Manager menu.
I went to your activation page and generated a key file xml. I put it in the P3D V4 folder and the GSX folder.
I don't know what page you are referring to, but nowhere we ever said you have to use an XML file or that you have to place it anywhere, much less in the P3D4 folder. I don't know what xml file you are referring to, the activation doesn't require any of that, and it's done automatically in the Addon Manager.
Could be you have a FIREWALL that is blocking the online activation, so you are trying some way to activate offline, using the QR code + smartphone method ? Even in that case, no XML files are involved, there's a self-guided method that surely works and doesn't require to do anything with any xml file.
In any case, as explained in the manual, you shouldn't use the forum to ask questions about activations because, of course, further troubleshooting would require sharing some of your personal details. Which is why, we clearly tell to use the support EMAIL for any questions related to orders or activation.
