Hello Umberto, Version 1.9.0.4 you mention is it for Vancouver scenery?
No, that would be GSX, sorry.
I am still having the Steam message after trying all your suggestions.
That's not possible, you must have some kind of registry keys mismatch in your system.
2) I launch the installer message comes up "Sim .EXE version is 10.0.61637.0 - This product requires FSX Steam Edition to be installed" I press okay.
It *seems* you HAVE the registry keys for the Steam version, they point to the FSX location and, since there's a regular FSX.EXE, the installer is telling you can't install there in "Steam mode"
Umberto as the installer is correctly finding my FSX install can I go ahead and install this update or not?
I'd say you can go ahead and proceed, because even if the installer found the Steam keys in the registry, it's not trying to install in Steam mode (because there's an standard FSX.EXE there), but in FSX mode.