I am experiencing the same issue. The add-ons I use are Ultimate Traffic, FSPassengers and FSUIPC. Ultimate Traffic still remains in the Add-on menu but everything else is gone. Like others, the NGX HUD dll installed at the beginning of the dll.xml file. I used Stacey's suggestion and that did not fix the problem. I then uninstalled the NGX, removed the HUD dll from the xml file and loaded the sim. My add-ons were still missing. I then tried to re-install the NGX and the add-ons are still missing. I am not sure what to do next? Any suggestions? Chris