Many apologies - My mistake, I typed FSGS when I should have typed FSX Ground Services.
Then I'm sorry, but it's not possible you would see this:
I had updated with the latest Addon Manager, the airport cache operated successfully but that was immediately followed by the message indicating a problem which was "could not find dll.xml"
This simply cannot happen, since nothing in the code that runs inside the sim ever tries to look the dll.xml, so you surely cannot have seen this "immediately" after the "Airport cache loaded successfully" message.
The only place where you COULD see a "could not find dll.xml", is in the installer. Which doesn't seem to be what you reported.