Why Am I Seeing This Error Message?

[vc-10man]

When trying to ask for any GSX Services, I see this crazy error message flourish itself across the top.

And yet the engines of this particular aircraft as can be clearly seen, are off.

Windows 10 Pro 64-bit, FSX-SE, Orbx scenery EGTE airport

Additionally, when starting FSX-SE, after this error had flagged, I got a warning right before FSX-SE could fire up about bglmanx.dll  causing a problem and a choice to run it or stop it.

[virtuali]

When trying to ask for any GSX Services, I see this crazy error message flourish itself across the top.  And yet the engines of this particular aircraft as can be clearly seen, are off.

This has been discussed so many times on the forum. Due to the non-standard flight model of the Q400, the variables GSX needs to read to know about the engine status are not updated normally on that plane.

You can use the CTRL+Shift+F1 ( default key combination to turn off fuel pumps ), which usually solves the issue.

[vc-10man]

I have not seen this being discussed here often because I have had no need to visit this particular Forum that often.

If it is an inherent issue with the Majestic Dash 8-Q400 flight model, why is that when I first tried to use the GSX service at another airport, it worked flawlessly? It was only when I tried to use the same GSX at another airport where I had landed the Dash 8-Q400, I saw that error flag. That is what baffled me.

Anyway, I'll bear your workaround in mind.

[virtuali]

If it is an inherent issue with the Majestic Dash 8-Q400 flight model, why is that when I first tried to use the GSX service at another airport, it worked flawlessly?

Because the status of the standard internal variables that holds the status of the engine, which are not used by the Q400, might depend on the previous flight or the airplane used in the last flight or in the default flight.

I confirm this IS an specific Q400 issue. You said "yet the engines of this particular aircraft as can be clearly seen, are off". The issue is, the engines being "off" in THIS particular aircraft, don't have an 1:1 relationship with the FSX default engine simulation, used by any other plane.

That's why CTRL+Shift+F1 will fix this, because it will put the FSX default engine variables back in sync with what you see.