Sorry. I misspoke when I said downloaded from Symantec server ... that should have been Symantec website - our licensing portal.
These are all unmanaged clients and have all (40+ clients so far) been installed previously with the standalone .EXE installer.
So I guess the question is, if the Windows Installer is not meant for the .EXE installer, then why does it open during the install?
At this point, I think I am going to revert one of these laptops to factory fresh and see what happens. Maybe there was a weird thing when these were imaged originally.
Thanks for all the advice so far.
Chris