Mattie941

For those that are interested, SteveFx's suggestion on the AVSIM forum has fixed my CTD issues: https://www.avsim.com/forums/topic/633405-appdll-crash-and-kb5025221/?do=findComment&comment=5039267

I see it mentioned here in a Microsoft support forum: https://answers.microsoft.com/en-us/windows/forum/all/fsx-apidll/33a02ac5-54ca-4643-98f8-2c7f10763b66 It is also mentioned in the support page: https://support.microsoft.com/en-au/topic/april-11-2023-kb5025221-os-builds-19042-2846-19044-2846-and-19045-2846-b00c3356-baac-4a41-8342-7f97ec83445a "You might have intermittent issues saving, copying, or attaching files using 32-bit apps, which are large address aware and using the CopyFile API." However, this may have been fixed in the June 11 update, but I have not had time to test yet. This update addresses a known issue that affects 32-bit apps that are large address aware and use the CopyFile API.

It has recently been confirmed that the API.dll crashes (IF no corrupt dll.xml file) are being caused by a Windows update from a few months ago. It’s a shame. I recommend everyone that is experiencing the issue to submit a support request with Microsoft: https://support.microsoft.com/en-us/home/contact This will help increase exposure to the issue and will hopefully expedite a hotfix.

A complete reinstall of Windows has not fixed the issue. Therefore I'm out of ideas... Thanks for the help John, but it looks I'm on indefinite leave.

I'm running off a clean install of FSX at the moment. I don't see another option other than a Windows reset unfortunately

Install log: FSUIPC4 Install.log Damn, it's more and more feeling like a Windows reset is going to be required...

Is this a P3D location, because it does not exist in my FSX root folder? I tried to install the FSX-XPACK SimConnect.msi files from both FSPassengers and Just Flight, but both files follow the same behaviour I descried above.

I tried uninstalling SimConnect but the latest version on the FSX Acceleration SDK is 10.0.61259.0. When I reinstall and start the sim, I still have the same mismatch. Therefore: How do I remove 10.0.61637.0 so that the FSX version matches? Or where do I find/download 10.0.61637.0 to update my SimConnect version I tried installing from Just Flight and from the Acceleration SDK. I run through the steps to install Acceleration SDK but when i run the SimConnect.msi, it still installs SimConnect 10.0.6129.0. It's strange because when I run the SimConnect.msi file, the "run as administrator" pop up asks if I would like to install SimConnect 10.0.61637.0 but then when I click "yes", the installer window appears it says SimConnect 10.0.6129.0. When I check for the version installed it is SimConnect 10.0.6129.0 and FSUIPC is still reporting a mismatch. The file properties of the Microsoft.FlightSimulator.SimConnect.dll file in "...\Microsoft Flight Simulator X SDK\SDK\Core Utilities Kit\SimConnect SDK\lib\managed"says that it is version "10.0.616.37.0 (FSX-Xpack.20070926-1421)" and yet it does not install this version. I'm not sure what I'm doing wrong? Found here: https://support.justflight.com/support/solutions/articles/17000100065-simconnect-files-for-fsx-p3d Apologies, it was poorly worded by me. The file I shared was before I implemented your "ProvideAIdata=No" and "NoWeatherAtAll=Yes" lines. I have experience the crash with and without these lines.

I have been running FSX from a fresh reinstall. Therefore the FSX.cfg, DLL.xml and EXE.xml are all stock files. I have not been able to recreate the crash from the fresh reinstall at the moment. I can only recreate the crash once I have installed FSUIPC (with NoWeatherAtAll ini parameter) and some addons to run using it: FSrealWX lite, FSFO v3, vasFMC 2.1, vPilot and Skytrack (my VA ACARS). The API.dll CTD does not seem to be related to any single one addon or combination of addons (I have tested with individual addons and combinations of addons).

It does not happen every time I load that flight plan. It does not seem to be linked to the flight plan. It can happen without a flight plan loaded or with a different flight plan loaded. Event viewer crash log: Faulting application name: fsx.exe, version: 10.0.61637.0, time stamp: 0x46fadb14 Faulting module name: API.DLL, version: 10.0.61637.0, time stamp: 0x46fadb58 Exception code: 0xc0000005 Fault offset: 0x0003afa2 Faulting process ID: 0x4308 Faulting application start time: 0x01d9b30461ae1c9f Faulting application path: D:\Program Files (x86)\Microsoft Games\Microsoft Flight Simulator X\fsx.exe Faulting module path: D:\Program Files (x86)\Microsoft Games\Microsoft Flight Simulator X\API.DLL Report ID: 51c241ba-652d-48e8-8c2d-2e625adba68e Faulting package full name: Faulting package-relative application ID: From Process Monitor, the last file FSX tries to read before "Thread Exit" is the kernel32.dll file.

Thanks for the quick reply John. I do not think that this is the issue because FSX loads FSUIPC fine and when I first run the sim, I was given the option to trust FSUIPC. I have managed to recreate the crash. The log and ini files are here (I have not implemented your recommendations in these files for the purpose of recreating the crash): FSUIPC.ini FSUIPC.log

Hi, I have been suffering from an API.dll CTD since the beginning of May. I detailed the crashes here: https://www.avsim.com/forums/topic/635654-fsx-apidll-crash-no-fixes-in-other-threads/?tab=comments#comment-4983809 When restarting FSX, I sometimes get an error messaging saying the FSUIPC is the cause of the crash and that it is not recommended to run the software. As one user suggests in the AVSIM post, could there be an issue with the new Microsoft update?