This sounds similar to a problem reported recently with the installation of the Eltima virtual port drivers on some versions of Windows. There are a few on-going discussions on the ap-gto forum now about a similar issue when installing on Window 7. The author of APCC thinks it is an Eltima installer problem.
Thank you for the info! I have a guess (and only a guess) to what the problem is. It does seems to be associated with the Eltima virtual port drivers. But, I also think it has to do with how I installed Windows 11 Pro. I used the free upgrade option and kept all of my third party software in place when doing so. Didn't find this problem until after the Microsoft 10 day rollback option had expired. To solve the problem, downloaded and installed on a USB stick a Windows 11 Pro .iso. Applied it to the laptop while keeping all third party software in place without success. So, did the "Crack a Walnut With a Sledgehammer" approach and wiped the laptop down to bare metal. This is one of the options during installation. Even deleted all partitions. Then installed Windows 11 Pro. After that the installation of APCC went smoothly and the problem with the Eltima virtual port drivers vanished. My guess is that the Windows 11 Pro upgrade from Windows 10 Pro does not play nice with some third party software. That's not much of a surprise. I'll figure out how to log into the AP user group and let them know what I found. Again, thank you! Clear Skies! 2b1af7f3a8