Can someone explain what these apps do in regard to the MD11?When I click on the FMS and any of the six screens on the MD11 many time my system crashes. I have reinstalled the MD11, changed video drivers and the problem still exists.If you think that FSX needs to be reinstalled can you explain why and how do you uninstall FSX because I can not find any way to uninstall FSXThanksDon L

You can uninstall most any executable either through the control panel or with the installer executable itself.Visual C++ is a runtime library installed by the pmdg installer, like most runtime libraries it contains procedures, methods or subroutines used by modules written in C++ such as the pmdg dlls.The MSXML is a Microsoft XML "interpreter" (for want of a better description) used by the OS to process xml.Net is a something developed by Microsoft that has many meanings, depending on context. In the most general sense, it acts as an interface between different processes.To fix the MD11 crashes, try running the MD11 installer and selecting Repair, both for the airplane and for the runtime library. If you are using Vista, be sure to run installer as administrator, and assign admin rights to the pmdg folder (under the FSX directory).Hope this helps, I am not a software expert so take the above definitions with some latitude.