I had this exact same problem, to fix it you do the opposite of what you would think... You actually have to exclude it from the airport elevation correction tool. Then is will go back to normal.

Have you all looked in the Scenery/world/Scenery folder for an elevation file for KSEA, usually the vector config tool will fix these but I've seen it wrongly disable an elevation that was needed.. KABQ for me.  If there's an elevation file and it's disabled with an .OFF or .inactive enable it, if active.. disable it with an .OFF and try.   The other thing to do is look for a duplicate airport for KSEA with airport scanner and disable it.  

Ok I have had the same problem and have found a good fix for it. 1. run VECTOR Configuration Tool.

2. Then check the priory level of the elevation file. to do this look at the scenery in fsx go all the way to the bottom of the list. If you find an orbx file almost at the bottom of the listed scenery files some were among the base scenery files then change it by putting it just below the vector files. I do not know why this happens but if you put it back up with the vector files then all will be well. Note the file can get put back in the wrong place again so if you get crazy elevation problems look for a miss placement of this file. Hope this helps.

Sir, the file you refer to ^^^ is supposed to be near the bottom of the scenery library.  It is in fact the file which contains all the AEC data and it is not in the wrong place as you state.  It's supposed to be there.  Running the sim will merely place it back where it belongs.

Simple solution here; first disable KSEA in the AEC tool and click apply then go to the ORBX Vector folders and in every folder search for KSEA and delete the entry, this will make sure the default airport background is shown again and the default altitude.

If still got a problem then go to the Terrain.cfg in your main FSX folder and search for all "airport_background" entries and change the "render priority" from 20.000 to 200.000 and if it has a mask class in the header then change the"Landclassremaptype from none into airport.

Very important note, don't ever open the FTX central any more or the terrain.cfg will be rewritten into the faulty one and all trouble starts again.

Herman

 

On 30.3.2017 at 9:28 AM, electricman said:

If still got a problem then go to the Terrain.cfg in your main FSX folder and search for all "airport_background" entries and change the "render priority" from 20.000 to 200.000 and if it has a mask class in the header then change the"Landclassremaptype from none into airport.

Very important note, don't ever open the FTX central any more or the terrain.cfg will be rewritten into the faulty one and all trouble starts again.

Thank you so much, Hermann!  

That solved the problem for me!

Now I made backups immediately of the corrected terrain.cfg file in case this annoying glitch reappears.

Have fun and take care

Scorpio47

 

P.S.
In general my experience with ORBX products is not as good as many suggest. They offer nice sceneries, no doubt about that, but their customer service SUCKS and as the case here demonstrates, some of their products are not really safe to use.

Edited March 14, 20188 yr by Scorpio47