On my PC I have the following Microsoft Applications:1. Microsoft.NET Framework 2.02. Microsoft Visual C++2005 RedistributableI believe that I have downloaded them for some reason which I do not remember, but I have recently had a number of 'runtime errors' when running FSX which have caused the simulator to crash.I do not know if I need them to run windows or if they are just for developers. If I delete them will my system come crashing down on me ?Any help will be greatfully received.The error occured again this evening. The full reported error was:Microsoft Visual C++ Runtime LibraryRuntime errorProgram:F:Flight Simulator Xfsx.exeR 6025- pure virtual functional callI think that the Microsoft Visual C++ was the program that had to be installed at the time of SP1 (vcredist_86.exe)If anyone can help I would be most obliged.

No add-ons?It appears that the link to the VS 2005 SP1 redist on finsider.com was wrong, you may want to try redownloading that and installing it.

Many thanks for your message.No add-ons? YES I have lots of military AI traffic, some 50 or so BGL's in SceneryWorldScenery.On the advice of another forum user, I have found that if I remove sufficient of them the problem will disapear, I would, however prefer to keep them all but maybe this cannot be?I took your advice and downloaded and installed the VA 2005 SP1, however, the problem still persists with all of my traffic in use.Is there a limit to how much traffic you can run? or is there a way to use lots of traffic without the 'runtime error' cutting in?If you can give me advice on this I would be most obliged.Best regardsJohn Cattell

Vista or XP?Physical RAM amount?One thing to try, ahead of FSX-SP2(DX10) is to use the tweaks for your OS and FSX to enable /3G. If its process address space you are running out of, this may help.

My current operating system is XP.My processor is the AMD Athlon64x2 Dual Core Processor 4600+2.41GHz, and I have 2.00 GB RAM Physical Address Extension.I am afraid that I dont understand what is required change the OS and FSX to enable /3G, or indeed, what '/3G' is ??? and I am not familier with'process address space'.Again, if you can help I would be most obliged.Thanks again.John Cattell

if you search, there are several threads with step by step instructions to enable /3G support in the main fsx forum.by default, 32-bit processes get only 2G of process address space. the /3G support, by tweaking the OS and the app, allows processes to use up to 3G of process address space and can reduce crashes if the app is using more than 2G.

Hi Phil,I have tried the /3G solution by entering the line '/3GB/userva=2560'into the boot.ini file, but the problem still persists.I am wondering if I tweeked the APP correctly!I went through Control PanelSystemAdvancedVirtual Memory and changed the Max to 2560, leaving the minimum to the original 768.I did at one stage change the min to 2560 as well and the max to 3070 but with no results. I carried out these changes to the C: drive only, although Flight Simulator X is on it's own drive (F:)Is this the correct way to tweek the APP?Is there anything else I can do?Many thanks for your help.John Cattell