I had the problem with the black smoke and contrails problem after deleting my ariane and LVL D aircraft and several others. I thought it was NGX issue until I found out deleting addon AC sometimes deletes those important files. Luckily I had a laptop to install FSX on so I could retrieve the files. Repairing had too many steps which I thought may screw up the FSX program. So I installed FSX with Aceleration which I didnt have to after all since the basic files are found on the regular FSX installation. I installed the SVC pack 1 and Acceleration anyway so I could have a pristine copy of gauges and effects. The files are: FX_1,FX_2, FX_3, FX_5 and the FX_smoke. If anyone needs them drop me an Email and I will send it through Email for you. It was a big pain in the butt trying to find them online but only a few actually were. None of my friends use FSX so I had to get them myself. Email at [email protected] and I will send them to you if you need them. If this is a violation of PMDG policy I apologize.

Upload to avsim? So long as you say the contents are strictly owned by microsoft etc etc. You should be okay

Files were uploaded to AVSIM, thanks for recommendation