That's what I was thinking. I have excluded my whole P3D folder, etc! I also disabled my antivirus. I just installed GSX a few days ago, maybe a week ago. This update is acting different
The installer is exactly the same as the previous one.
The one acting differently is your antivirus, maybe because the installer is "new", so your antivirus is not trusting it, based on some flawed heuristic that assume that a new file doesn't have enough "reputation" to be considered trusted, even if we digitally sign all our executables, and we add a specific standard digital signature (called Taggant) to PREVENT antivirus to catch false positives.
I can only confirm the problem doesn't happen: I've just ran the installer now, and it worked normally with no errors.