FSX Error with ModelconverterX 1.70 for FSX

[PhotoBird]

GaryGB, I will act on what you just now posted and see if I have any success. Thanks again for your help and if you don't hear back from me that I've been successful bring this to Arno's attention when you have contact with him. Maybe he can ID what my problem is. I know both of you are WAY more knowledgeable about this stuff than I am.

 

[PhotoBird]

Just to follow up, I downloaded and installed DirectX 9 and I'm still getting the same black-screen fatal error message as I posted before.

 

[rhumbaflappy]

The problem is not with MCX. Hundreds (maybe thousands) use MCX without start problems.

Use Windows File Explorer to delete your MCX folder and it's contents, where ever you put it.

Then use Windows File Explorer to find the config file folder: C:\Users\username\AppData\Local username is your windows username. (You can type %appdata% in file explorer and you get the Roaming folder... then hit the Up Arrow to go up in the directory tree to find Local...) then find SceneryDesign.org Highlight and then delete that folder. Now you have a new installation as it gets rid of the config file. MCX will rebuild that folder when you open it.
Unzip MCX to a new folder (maybe C:\Programs\ModelconverterX). Run the program.

If this doesn't work on your Windows 10, then there may be a problem with Windows.

 

[PhotoBird]

Rhumbaflappy, thanks for the post. I know MCX is not the problem here, gotta be some interface glitch. I followed your instructions... Removed and reinstalled MCX v. 1.8, deleted SceneryDesign.org folder from AppData, tried to start MCX and still got the same black-screen fatal error message from my previous start-up attempts. I wish I knew what computer event (or action by me) killed MCX v. 1.7 when it had not even been recently opened by me. That's what caused me to post here. Only thing I've done to the PC in the past few weeks was to install a new GPU (NVIDIA GeForce GTX 1070) and it has caused me no problems with FSX, FS9, or anything else I've accessed.

 

[GaryGB]

We'll get to the bottom of this eventually; hang in there.

GaryGB

 

[PhotoBird]

We'll get to the bottom of this eventually; hang in there.

GaryGB

GaryGB, thanks again.

 

[arno]

Hi,

Just returned from my vacation. And I need to correct some incorrect information in these discussions.

Version 1.8 of MCX does indeed use .NET 8.0, while version 1.7 uses .NET Framework 4.8. But unlike Gary posted, MCX does not require you to install the .NET SDK. You only need to install the .NET runtime files.

The manual that comes with MCX does provide all information on the prerequisites in section 3.1 and it does also include download links so that you can download them directly. MCX itself only needs .NET and the C++ runtime files. Depending on which SDK version you are using you might have other prerequisites, but technically speaking these are SDK prerequisites and not MCX prerequisites.

The last posted error message does seem to indicate issues with the OpenGL support. What kind of operating system and graphics card is being used here?

The error message in the first post seems to be different. That error message looks very similar to a bug that has been reported multiple times in the bug tracker, but that I never was able to reproduce. I think it might be related to specific Windows localisation settings or language specific settings. So if @Franzi can let me know which OS and which language he is using I can have another look at trying to reproduce it.

 

[GaryGB]

Hi,

Just returned from my vacation. And I need to correct some incorrect information in these discussions.

Version 1.8 of MCX does indeed use .NET 8.0, while version 1.7 uses .NET Framework 4.8. But unlike Gary posted, MCX does not require you to install the .NET SDK. You only need to install the .NET runtime files.

The manual that comes with MCX does provide all information on the prerequisites in section 3.1 and it does also include download links so that you can download them directly. MCX itself only needs .NET and the C++ runtime files. Depending on which SDK version you are using you might have other prerequisites, but technically speaking these are SDK prerequisites and not MCX prerequisites.

Hi Arno:

Thanks for the reminder that MCX prerequisites are now to be found in the MCX PDF Manual in the MCX install folder.

MCX current development release is August 4th, 2025, and shows prerequisites on Page 10:

3.1 Prerequisites
Before you install ModelConverterX, please make sure that you have the following prerequisites
installed on your computer:
• A graphics card capable of supporting OpenGL 3.3
• Microsoft .NET 8.0 x64.
• Microsoft Visual C++ 2015-2019 runtime files. If you run a 64 bit operating system, make
sure to get the x64 version, else get the x86 version.
• To be able to export files in the formats used by FS2004, FSX or Prepar3D you need the
Software Development Kit (SDK) of the specific flight simulator version you are working
with.

The link to .NET 8.0 x64 takes the would-be MCX user to:

https://dotnet.microsoft.com/en-us/download/dotnet/8.0

.NET Desktop Runtime 8.0.19​

The .NET Desktop Runtime enables you to run existing Windows desktop applications. This release includes the .NET Runtime; you don't need to install it separately.

OS	Installers	Binaries
Windows	x64 | x86 | Arm64 | winget instructions

Downloads for .NET 8.0 Desktop Runtime (v8.0.19)


'If' would-be MCX users understand they should select .NET "runtime" versus "SDK" version, and that it is not now "time to run", they 'may' know that they should click this link:

https://dotnet.microsoft.com/en-us/.../runtime-desktop-8.0.19-windows-x64-installer

...instead of the one I posted earlier in this thread because I was hoping that the SDK version may get MCX 1.8 to 'work'.

AFAIK both .NET SDK and RunTime versions 'should' work OK as they both contain components that MCX requires to run.


As you may know, having a custom error report generator for .NET code apps may help non-programmers help themselves.

But as we are at the mercy of JIT-compiler 'gobbledygook' incomprehensible to most end users of MCX, we must ask your help.

Since we have not yet solved getting MCX to run for PhotoBird, we are still compelled to ask you as author of MCX:

...what else might we do to troubleshoot his MCX 1.8 installation ?


Thanks in advance for your further insight into what we need to do in order to get MCX working on PhotoBird's computer.


PS: Have you considered adding a routine to MCX when first run to copy and open the MCX Manual from the Desktop ?

By now as a programmer, you know that very few end users ever look for- and actually read- "Read_Me" files, and even fewer are inclined to "RTFM", in spite of having available, a manual as good as the one you so kindly provided with MCX.

That is why I suggested putting prerequisites for MCX on a separate page as your development releases are all on (1) page.


Demographics in the FS world are changing; in spite of MS' hopes to attract younger "Gamers", FS ...is for older 'Geeks'.

AFAIK, a majority of FS and MCX users are increasingly less likely to be either younger- or highly experienced- computer users.

Thus, we see increasing participation here from folks who may benefit from things being explained in easier to follow formats.

FSDeveloper displays flags for country of origin for forum participants, and we also have the 'option' to display declared age.

I believe it is time for FSDeveloper to also 'develop' a greater sensitivity to the needs of the 'older majority' of its visitors / users.

GaryGB

 

[PhotoBird]

The last posted error message does seem to indicate issues with the OpenGL support. What kind of operating system and graphics card is being used here?

Hi Arno,
I assume you're referring to my error problem here. My OS is Windows 10 Home (x64), v.22H2 (build 19045.6216). Graphics card is NVIDIA GeForce GTX 1070, current driver is v.580.97 released 8-12-25 and installed by me 8-28-25 as part of troubleshooting this MCX error. The card itself was installed a couple weeks ago and has caused no problems with anything else.

My old graphics card was a NVIDIA GeForce GTX 550 Ti that I used since I built my rig in 2011. Last time I used MCX I still had the old card installed if you're thinking maybe the new card's OpenGL isn't playing well with MCX. I think I did everything right when I uninstalled the non-working v.1.7 and installed v.1.8 which didn't work either. Any suggestions you may have will be most welcome. MCX is a good FS tool and I'd like to get it back up and running.

 

[GaryGB]

Hi again:

Just an FYI, when looking through the implications of your MCX version 1.8 startup error messages, I had looked at the specs for your video card posted on Page 1 of this thread, and had confirmed it meets the current version requirements of MCX by supporting OpenGL version 4.6, which is future-ready for upgrades of MCX that may still be only a sparkle in Arno's eyes.

GaryGB

 

[arno]

'If' would-be MCX users understand they should select .NET "runtime" versus "SDK" version, and that it is not now "time to run", they 'may' know that they should click this link:

https://dotnet.microsoft.com/en-us/.../runtime-desktop-8.0.19-windows-x64-installer

...instead of the one I posted earlier in this thread because I was hoping that the SDK version may get MCX 1.8 to 'work'.

I will update the manual to state clearly you need the x64 desktop runtime to run MCX.

As an end user you will not need the SDK tools, these are only for developers making .NET applications and to run the applications all you need are the runtimes.

As you may know, having a custom error report generator for .NET code apps may help non-programmers help themselves.

But as we are at the mercy of JIT-compiler 'gobbledygook' incomprehensible to most end users of MCX, we must ask your help.

Since we have not yet solved getting MCX to run for PhotoBird, we are still compelled to ask you as author of MCX:

...what else might we do to troubleshoot his MCX 1.8 installation ?

Like I posted yesterday, I suspect it is OpenGL related if I look at the stack trace. So therefore I asked PhotoBird what kind of graphics card he is running so that we can see if it meets the minimum OpenGL specs of MCX.

I don't see how custom error reporting would help here, as I can never predict beforehand which errors will be throw on all the systems of the end users and it is this stack trace that gives me the best information to help users further on the forum as it shows me in detail where problems occur.

PS: Have you considered adding a routine to MCX when first run to copy and open the MCX Manual from the Desktop ?

By now as a programmer, you know that very few end users ever look for- and actually read- "Read_Me" files, and even fewer are inclined to "RTFM", in spite of having available, a manual as good as the one you so kindly provided with MCX.

That is why I suggested putting prerequisites for MCX on a separate page as your development releases are all on (1) page.

If I put this kind of information on multiple places it is much harder for me to keep it up to date, that's why I have decided to put it in the manual only. If an application does not start, I think it is a reasonable assumption that the end user will check the manual for additional information (although of course I also always first try before I read a manual).

Opening the manual at first start will be annoying I think and MCX already has a button where you can open the manual directly from the application.

I assume you're referring to my error problem here. My OS is Windows 10 Home (x64), v.22H2 (build 19045.6216). Graphics card is NVIDIA GeForce GTX 1070, current driver is v.580.97 released 8-12-25 and installed by me 8-28-25 as part of troubleshooting this MCX error. The card itself was installed a couple weeks ago and has caused no problems with anything else.

That graphics card does support the OpenGL version that MCX uses, so that should not be the problem. The error comes from the library I use to deal with the OpenGL rendering of the 3D preview. Let me see if I can find information on additional dependencies of that library.

 

[PhotoBird]

Hi again:

Just an FYI, when looking through the implications of your MCX version 1.8 startup error messages, I had looked at the specs for your video card posted on Page 1 of this thread, and had confirmed it meets the current version requirements of MCX by supporting OpenGL version 4.6, which is future-ready for upgrades of MCX that may still be only a sparkle in Arno's eyes.

GaryGB

Thanks, GaryGB, I didn't see any options on the NVIDIA control panel that I felt comfortable messing with so I appreciate you confirming the OpenGL capabilities of the new graphics card.
I wish my original "Error Handler" error message had listed a location of the problem like on Franzi's post. Just telling me there's a problem doesn't help much. One other comment: I also tried old MCX version v.1.5 Friday night and I know I have all the prerequisites installed for that version and now it caused that Error Handler message too.

 

[GaryGB]

IIRC, by default, MCX stores configuration data in a specific and centralized location for any and all versions of MCX one may use.

IIUC, we have an option in MCX that allows us to store MCX installs as separate and discrete entities, with configuration settings in their own location.


Perhaps Arno might update us on how to use that MCX option so that each version of MCX located on our computers does not share common settings ?


I recall doing this years ago, and it helped maintain control over a rogue MCX installation that had gone horribly wrong, and was later fixed by Arno.

While awaiting a fix of the development release with problematic issues, I used either of (multiple) older installs of MCX with impunity, and got things done.

GaryGB

 

[arno]

Perhaps Arno might update us on how to use that MCX option so that each version of MCX located on our computers does not share common settings ?

No, that's just how .NET stores it settings. So unless I implement that logic fully by myself (on which I don't want to waste time), they will remain shared.

 

[arno]

@PhotoBird so on both version 1.7 and 1.8 you get the same error message at startup and it is still the same as posted on page 1?

 

[PhotoBird]

@PhotoBird so on both version 1.7 and 1.8 you get the same error message at startup and it is still the same as posted on page 1?

Arno, thanks for your help. When I attempted to run MCX 1.5 and 1.7 I got the original Error Handler message from my original post: "An unexpected error occurred." After I installed .NET 8.0 and tried to start MCX 1.8 and got the three EULA/copyright "I agree" screens you see when MCX starts up (looked like it was starting) but after my last "agree" click there was a pause and then I got the black-screen "fatal error" message I attached in posts #16 and #18 earlier in this thread. With .NET 8.0 and MCX 1.8 installed that's what I keep getting now.

 

[arno]

Did you press the report error button in 1.7? Then I can check if the details of the error are the same.

For 1.8 it seems to be a OpenTK issue (that's the OpenGL library I use). But this is the first time I have seen that issue. So I need to check what it means.

 

[PhotoBird]

Did you press the report error button in 1.7? Then I can check if the details of the error are the same.

For 1.8 it seems to be a OpenTK issue (that's the OpenGL library I use). But this is the first time I have seen that issue. So I need to check what it means.

Give me a couple minutes with MCX 1.7 installed and I'm pretty sure I can duplicate the Error Handler message and I'll be sure to click the "report error" button.

 

[PhotoBird]

UPDATE: Arno, I just now attempted to run MCX 1.7, got the same "Error Handler" prompt as before, and this time made sure to hit the "send report" button. Hope that helps you.

 

[arno]

I got it in the error tracker now, it is a different error from version 1.8, but still has to do with the initialisation of the OpenGL control. So I think it must be something related to the graphics driver on your system.

Do you maybe have multiple graphics card (also one on the motherboard maybe)?