How do you un-install addon scenery????

I tried deleting it, but then it would have an error saying "cannot load file such and such"

You say delete,how?
Have you deleted the scenery from scenery settings in fs9?
Or have you just deleted the scenery file?

I deleted the whole file from the Addon Scenery folder

Have you also gone into Settings/Scenery Library and deleted the appropriate entry there

Yes, you must delete from the scenery settings in fs9

fire up fs9 then goto settings/scenery.now find the scenery you dont want and delete using the options on the right hand side
That should cure your problem

There is no real need to delete scenery folders,just uninstall it from fs9

Thanks guys that solved the problem!