I noticed in reviewing my FSDT airport listings via the AddOn Manager in FSX that my Hawaiian Airports Vol 2 was active but not installed. So I downloaded the latest Vol 2 file. During installation I got a "DeleteFile failed: code 5" message having to do with the alut.dll file in my FSX\FSDreamteam\couatl folder. My choices were to "Retry", "Ignore" (not recommended) or "Abort".
As explained in many other threads on the forum, that message means you launched the scenery installer too quickly without waiting for FSX to properly close, and some files were still releasing locks.
A reinstall after Windows reboot will surely fix this.