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Unable to convert MCX.dll.issue

Hi everybody,
so Im trying converting some planes to static as well for our scenery project. I went through the forum and the thing about changing language but in my case it didnt help and Im still getting Unable to convert this model for use with FSX MCX.dll issue error.

What shall I do?

RUnning WIn 7 64bit, FSX.



Resource contributor
SAMM uses a number of ModelConverterX .dlls (included) in the conversion of aircraft models to static models when the "vintage" of the aircraft model differs from the target FS version (e.g., converting a FS9 aircraft for use with FSX, or vice versa). This error message is issued when such conversion, for whatever reason, cannot be accomplished. Generally, if not preceded by some other error message, it means that some characteristic of the aircraft model is very unusual.

If you send me the aircraft folder (I only need a single texture) or a link to the source from which you obtained it, I'll investigate.

Im not at my PC at the moment. But I was trying to convert any Gulfstream from SKY AI package for example. Will send you the file when I get home if you dont have SKY AI.

Thank you


Resource contributor
Please do. If it's freeware, all I need is a link and the culprit aircraft identified.



Resource contributor
I've had a look at the Sky AI site. I have no interest in downloading and installing such packages on my system. Please send me that aircraft folder with a single texture, which should keep the file size reasonable. BTW, I assume you were trying to convert a FS9 aircraft for FSX.



Resource contributor
The current release of SAMM converts that aircraft for FSX for me without difficulty.

Do you have the FSX SDK installed? Are there any other error messages, perhaps advising you of missing files,. prior to the one to which you referred? Have you updated any of the MCX .dlls included with SAMM? Have you tried re-installing SAMM?

Strange :( Yes I do have SDK installed. Tried to redownload SAMM ans dtill no success. BTW where the MCX.dll file should be located I didnt update it anyhow. Here is my SAMM config file. Maybe theres something to see:

Default Units(Posn) is DDdddd=False
Default Units(Posn) is DDMMmm=False
Default Units(Posn) is DDMMmm=False
Default Units(Alt) is Ft=False
Listings and Tools=False
Last Folder - Scenery Save for FS9=
Last Folder - Scenery Save for FSX=
Last Folder - Scenery Save for PV1=
Last Folder - Scenery Save for PV2=
No Automatic Updates=False
Last Update Checked=
Default Model Posn - Lat=0
Default Model Posn - Lon=0
Default Model Posn - Hdg=0
Dedicated Textures=False
Don't Use "All" Folders=False
Path to MakeMDL=
Path to XToMdl.exe (FSX)=
Path to XToMdl.exe (PV1)=
Path to XToMdl.exe (PV2)=
Warn if FSX Model->FS9 Scenery=True
Use FS9 Global Variables=False
Path to FS9=
Path to FSX=C:\Games\Microsoft Flight Simulator X
Path to PV1=
Path to PV2=
Path to FSX SDK=C:\Program Files (x86)\Microsoft Games\Microsoft Flight Simulator X SDK\SDK
Path to PV1 SDK=
Path to PV2 SDK=
Path to FSX Compiler=C:\Program Files (x86)\Microsoft Games\Microsoft Flight Simulator X SDK\SDK\Environment Kit\BGL Compiler SDK\bglcomp.exe
Path to PV1 Compiler=
Path to PV2 Compiler=
Path to ImageTool=
Version Flag for Last Scenery Compile=-1
Aircraft Select=-1
Last edited:


Resource contributor
Perhaps not. I notice you have FSX and the SDK installed on your C: drive. I suspect you've done the same with SAMM. Are you "running as administrator"? Simply having administrator privileges isn't adequate.



Resource contributor
Then I don't know what else to suggest. We know the aircraft itself is not the problem because both George and I can convert it without difficulty. That make me suspect it's due to something on your system. But if you are running as administrator, I can't imagine what it might be - assuming SAMM is installed properly and all the supplied .dlls are present in the SAMM folder.

Try doing a basic conversion , i.e., for FS9. Unless there are transparency issues, the static model should still display properly in FSX.

Where should the magic MCX.dll be? Here is screen of my SAMM folder.



Resource contributor
There is no single "magic MCX.dll". Most of the .dlls in that folder are MCX dlls, i.e., a .dll from MCX (used with Arno's permission). The message you received is that one of them reported an error. But, since the aircraft converts without difficulty for me and your date stamps are the same as mine, I doubt any of them are directly responsible. Rather, I suspect something in your system configuration is preventing them from doing their job. But, since no one else has, to my recollection, reported such an error - certainly not recently - I have no idea what that could be. other than insufficient privileges, which is why I asked about running as administrator.

If anyone else has thought on the matter, please jump in.



Resource contributor
I'm surprised. No one else has reported any such difficulty lately. SAMM already handles "," to "." conversion where we know it is necessary. Do you have any idea what aspect of the data needs attention? Did you make any entries including a comma as a decimal separator? If so, do you remember where?