Rider is attempting to launch the wrong Unreal Engine version

Nevermind, deleting the project's Intermediate folder and then regenerating project files fixed it.

Hello,

Thank you for contacting Rider support and for sharing your experience.

It looks like you encountered this known issue: RIDER-118192 Rider quietly builds against an older version of UE than the .uproject says.

After switching the engine version and opening a project in Rider, Rider needs to re-generate Unreal project files (it does it automatically by invoking GenerateProjectFiles script or by calling UnrealBuildTool with a specific list of arguments (depends on OS and engine version)). 
The output of this process is .json files under the /Project/Intermediate/ProjectFiles/.Rider folder. These .json files are used further to generate a project model and finally to generate/update Run Configurations. I assume something went wrong during this process.

It is unlikely we can now troubleshoot why exactly this process failed for you. (We need UBT logs for that or the output from the UnrealBuildTool tool window). Possible reasons are mentioned on the issue page, and we hope to address this problem in future releases.

Removing the Intermediate folders, indeed, can help in such a situation. I am glad to know you found this solution.

Should you have any other questions or difficulties in the future, do not hesitate to contact support.

Have a nice day!

I see, thanks for the reply Dmitry Kazantsev . While I have fixed the issue indeed, here is some info that may help you track down the issue.

• Project was created in UE 5.4.4 (Launcher version)
• Project was updated to 5.5 via the uproject context menu (Switch UE version). Rider was closed when I did that.
• Pressing the refresh button in Rider did not solve it.
• Project contains plugins inside its own project folder (ProjectFolder/Plugins)
• Rider build: Build #RD-233.14015.60, built on January 18, 2024
• I have both VS 2019 and 2022 installed on my machine
• I have the following text in my AppData\Roaming\Unreal Engine\UnrealBuildTool\BuildConfiguration.xml file:

<?xml version="1.0" encoding="utf-8" ?>
<Configuration xmlns="https://www.unrealengine.com/BuildConfiguration">
   <WindowsPlatform>
       <Compiler>VisualStudio2022</Compiler>
   </WindowsPlatform>
   <VCProjectFileGenerator>
       <Version>VisualStudio2022</Version>
   </VCProjectFileGenerator>
</Configuration>

ss

If you think these logs may be backed up somewhere, let me know where to look. 

I looked in \AppData\Local\UnrealBuildTool but strangely enough, could find only the logs from after the issue was fixed, as well as some backup logs dating from as far back as 2020… The one you actually need is not on that folder unfortunately.

Hello,

I suspect these (ProjectFolder/Plugins) plugins led to the issue. Are these plugins from Unreal Marketplace or other publicly available those? (if so, please share its names).

Meantime, we could have a look at the logs from "C:/Users/Username/AppData/Local/UnrealBuilTool"

Would you mind sharing this whole folder? Please, upload it to the Upload Service and let me know the Upload ID.

Have a nice day!

Ah, I just noticed you looked under this folder already. If there are actually no backup logs for the necessary day, we unlikely could determine the exact cause of the issue occasion on your machine.

PS. While verifying this issue, I noticed one more related problem. I reported it to our tracker: RIDER-120682.
This is a subcase of the issue you encounter. The wrong executable path is displayed even when there were no errors during the process I described earlier. However, it switches to a proper executable shortly after Run, Build or run configuration switch is invoked. In short, this is a UI not updated, while all the actual used paths are correct and used as expected.

Dmitry Kazantsev yes, plugins from the marketplace. They are these:

Yeah that folder has nothing from when this bug happened, I looked by date modified and did a search for “5.4” in possible suspects. Nothing found.

Hello,

Apologies for keeping you so long without a response.

Unfortunately, I couldn't reproduce the issue in my environment. Since we have no logs for the period when the issue occurred, we, unfortunately, can't determine the exact cause of the issue, and I am going to close the ticket now.

If such an issue occurs again in the future, I would appreciate it if you could dump and share the following information:

• Archive the /Project/Intermediate/ProjectFiles/.Rider folder (or the whole /Project/Intermediate/ProjectFiles/);
• Archive the C:/Users/Username/AppData/Local/UnrealBuilTool folder;

• Dump the output from the UnrealBuildTool toolwindow to a text file:

  

• Ensure the Exe path in run configuration remains unchanged (and wrong) after building the project;

  

• Ensure and confirm the wrong UnrealEditor.exe starts:

  

• Contact us again and share this data;

Should you have any other questions or difficulties, do not hesitate to ask.

Have a nice day!

I ran into a similar issue upgrading from Unreal Engine 5.3.2 to 5.5.1

I saw a mismatch in the Run/Debug Configurations panel, but removing my Intermediate and Plugin folders was enough to resolve that issue, but I also noticed quite a bit of feedback during Rider's project processing, resolving these issues by updating my specific target.cs files fixed my issue completely.

09:59:30.423: Warning: [Upgrade] Using backward-compatible build settings. The latest version of UE sets the following values by default, which may require code changes:
09:59:30.423: Warning: [Upgrade]     bLegacyParentIncludePaths = false               => Omits module parent folders from include paths to reduce compiler command line length. (Previously: true).
09:59:30.423: Warning: [Upgrade]     CppStandard = CppStandardVersion.Default        => Updates C++ Standard to C++20 (Previously: CppStandardVersion.Cpp17).
09:59:30.423: Warning: [Upgrade]     WindowsPlatform.bStrictConformanceMode = true   => Updates MSVC strict conformance mode to true (Previously: false).
09:59:30.423: Warning: [Upgrade]     bValidateFormatStrings = true                   => Enables compile-time validation of strings+args passed to UE_LOG. (Previously: false).
09:59:30.423: Warning: [Upgrade] Suppress this message by setting 'DefaultBuildSettings = BuildSettingsVersion.V5;' in MyGameEditor.Target.cs, and explicitly overriding settings that differ from the new defaults.
09:59:30.423: Warning: [Upgrade]
09:59:30.423: Warning: [Upgrade]
09:59:30.423: Warning: [Upgrade] Using backward-compatible include order. The latest version of UE has changed the order of includes, which may require code changes. The current setting is:
09:59:30.423: Warning: [Upgrade]     IncludeOrderVersion = EngineIncludeOrderVersion.Unreal5_3
09:59:30.423: Warning: [Upgrade] Suppress this message by setting 'IncludeOrderVersion = EngineIncludeOrderVersion.Unreal5_5;' in MyGameEditor.Target.cs.
09:59:30.423: Warning: [Upgrade] Alternatively you can set this to 'EngineIncludeOrderVersion.Latest' to always use the latest include order. This will potentially cause compile errors when integrating new versions of the engine.
09:59:30.423: Warning: [Upgrade]
09:59:30.423: Warning: [Upgrade]
09:59:30.423: Warning: [Upgrade] The latest version of UE no longer supports CppStandardVersion.Cpp17 which may require code changes.
09:59:30.423: Warning: [Upgrade] Suppress this message by setting 'CppStandard = CppStandardVersion.Cpp20;' in MyGameEditor.Target.cs.
09:59:30.423: Warning: [Upgrade]
09:59:30.423: Exception while generating include data for Target:MyGameEditor, Platform: Mac, Configuration: Development

Nothing beyond RiderLink, I don't use any non Epic plugins shipped inside UE 5.5.
I really think this came down to a build target c# issue with the changes that were expected.

Hello warbands ,

Thank you. Should such an issue occur again, I would appreciate it if you could share diagnostic information as I described above.

Have a nice day!

Additional note: Do I understand correctly that attempting to run a project from Rider after switching the engine does not launch Unreal Editor of a newly retargeted version? So, you switched engine to 5.5 (via right-click on .uproject), then opened the project in Rider, tried to run/build it:

• Does the previous unreal editor version start in this case?
• Does run and build output show the wrong paths (to UE 5.3.2 binaries) to be used?

Yea, sorry I had it resolved before I thought about trying to put diagnostics up here.

In regards to the additional note:

Your process listed above is correct and is what I had done. It does indeed run the previous editor version if I start it from Rider, and the output does indeed show that all paths were pointing at UE 5.3.2

Once I closed Rider, removed the Intermediate folder and restarted Rider, cleaned the solution and rebuilt, that is when I saw the list of things that needed to change in my various build target C# files. Once that had been completed I was able to compile and launch against UE 5.5.1

Hope this helps.