P3D v4 Beta with Prepar3D v4 support

Cheers for that. You are right in that there's really no need to check for scenery via add-on.xml, simply because if a scenery is added this way, it may as well add the autogen descriptions file link in the xml file as well.
So with P3D v4 it is really only necessary for adding custom autogen to legacy scenery.
Hello Arno

after a quick test, it only appears to merge as you described only during the initial install of Autogen Configuration Merger from within the Command prompt.

after the initial install when the Configuration Merger is run during P3dV4 start up it only merges the AutogenDescriptions.spd but not the AutogenDescriptions_Legacy.spd

can you confirm this or am I doing something wrong?



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FSDevConf team
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Sounds like the version of the sim was not detected correctly in that case. Do you see in the log which version was detected? I'll check the code...


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FSDevConf team
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OK, I have uploaded a new beta that should fix the problem and detect P3D v4 correctly as well when not ran in install mode.
HI Arno

as above still the same after the initial install , during P3d v4 Start up although Autogen Configuration Merger starts up and merges the default.XML and other files there, is still does not merge with the AutogenDescriptions_Legacy.spd , it only appears to merge with the AutogenDescriptions.spd.

can I also ask where is the log located?



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FSDevConf team
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Check the included manual for the log location, it's in your AppData folder. The log might help to tell us what is going on.


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Humm, I see, it seems to have detected the autogen configuration files already before it detect the version is Prepar3D v4. I'll check the code again tonight.
Hello Arno

I don't know if this may be useful, the first log is during the initial install of the Autogen Configuration Merger with a default Autogen folder in P3d V4
the second log is of the Autogen Configuration Merger during the P3dv4 start up again with a default Autogen folder in P3dv4. the latter does not appear to update the _Legacy file where as the initial install does.

BTW this is for information, I have just copied and renamed the descriptions file as _Legacy which is working for me at the moment. I hope this is of some help to you.



I must admit that I did make a rookie mistake, and somehow ended up keeping ACMT-merged descriptions active when I thought that my add-on.xml file was supplying my custom trees. But as has been pointed out here, it doesn't work that way. I had hoped that I could get away without making a single change/addition to the Prepar3d installation folders, but it isn't as simple as I thought.

The ideal solution might be to use ACMT to merge my descriptions with the default, but save them in my add-on folder. On the other hand, one of the reasons why I like and use ACMT is that other developers change the default files anyway, so I'll probably just carry on as usual, installing ACMT with my scenery, and running it as I've done with FSX and P3Dv3. The only problem here is that I can't add my scenery using add-on.xml, as ACMT doesn't pick it up when it runs.

So it's back to the drawing board, installing scenery using the command-line method. Has anyone come up with a better solution?

At the moment, I have a merged descriptions file in a folder pointed to by add-on.xml, I just need a way to get it there for my users.
Hello Arno

Having looked at the logs I noticed I wasnt using the latest version 1.0.6391.34614

I have now tried the latest Beta version now and all appears to work as it should, during
the initial install and during the P3d V4 start up.

Thanks for your trouble and thanks for a fantastic utility for FSX & P3d

its nice to have add ons working together side by side.



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FSDevConf team
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Ah, glad to hear that. I didn't have the time yet to debug the apparent issue. Glad it's solved.
For some reason I am unable to get the beta version of the autogen config merger to start (and merge) when I start P3D v4. The message that is supposed to come up stating that the autogen files are merging does not show up. My scenery has an autogen folder with an spb file, it is present in the scenery library and the autogen merger is installed with a valid entry in the exe.xml file. Any ideas what might be wrong?

The autogen config merger I believe does no check the XML it only checks the Addon Scenery.cfg file.

I have it working flawlessly, however to do this I have created a folder for Autogen files autogendescription.spd files ect.

Folder (Scenery name)

Folder (Autogen)

Autogen Files(AutogenDescriptions.spb)

Folder (Scenery)
Leave empty

I have then added the folder (scenery name) to addon scenery via the scenery library tool within P3d menu World - Scenery library

Hope this is of help
Yes, I ended up doing the same with my v4 updated installers, my autogen descriptions are not attached to a particular scenery, they belong with the scenery libraries, so all my scenery is activated via add-on.xml, but the libraries are added to the Scenery Library via the command-line, so that the merger tool can find them.
I have a folder named autogen and my scenery is in the scenery library. I have tested the beta autogen config merger with P3D v3 and it works perfectly, but with P3D v4 it does NOT work for some reason. I wonder why, it is working for everyone else?
OK, I figured out what was wrong. In P3D v4 I had another add-on scenery which edited the default.xml (in the P3D v4 main autogen folder) from its original state. For some reason, this caused the autogen configuration merger to not work. I restored the original default.xml back and then the autogen merger worked for my scenery.


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I mistakenly edited the exe.xml in %programdata% instead of %appdata%. It seems having the entries for ACM in both location causes the app to crash (possibly due to a dual startup.)


I'm getting an I/O crash from ACM as soon as it opens via P34. (Whether there is new autogen or not).

Problem signature:
  Problem Event Name:    CLR20r3
  Problem Signature 01:    AutogenConfigurationMerger.exe
  Problem Signature 02:    1.0.6391.34614
  Problem Signature 03:    5957e67a
  Problem Signature 04:    mscorlib
  Problem Signature 05:    4.7.2053.0
  Problem Signature 06:    58fa6bd6
  Problem Signature 07:    165d
  Problem Signature 08:    1d7
  Problem Signature 09:    System.IO.IOException
  OS Version:    6.1.7601.
  Locale ID:    1033
  Additional Information 1:    0a9e
  Additional Information 2:    0a9e372d3b4ad19135b953a78882e789
  Additional Information 3:    0a9e
  Additional Information 4:    0a9e372d3b4ad19135b953a78882e789

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Most times the error log showed no errors, meaning it crashed after it had processed through the scenery.cfg. I thought it might have been a problem with my custom autogen files so I removed them, but the crash still occurs, and now writing to the log seems to stop halfway in its tracks. (Find attached).

This does not occur in P33. Also, I had ensured that I had the latest version and updated from 1.0.6365.11790 to 1.0.6391.34614. I can confirm that this crash occurs in both versions.

I will continue to see If I can find more details as to what changed on my system as this was not happening a month ago.


Last edited:
Hi Arno,
for some reason ACM doesn't detect P3D v4.1 when I install it. It sees only my FSX installed on the same rig, all other options are greyed.
How could I solve the problem? On which file/directory/registry key does ACM rely on to give us the choice?