Resolved Can't debug on HL1; missing WindowsMRXRSDK DLL?

Unity 2020.3.8f1, project configured to use Windows MR XR plugin on UWP builds. Hololens 1, debug build x86, in Visual Studio, try to run on Remote Machine (to the HL1), deploys with no errors, window opens on HL1 but is blank, application fails to start with last error in log:

Code (csharp):

1. Exception in callback: System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.DllNotFoundException: Unable to load DLL 'WindowsMRXRSDK': The specified module could not be found.
2.   at UnityEngine.XR.WindowsMR.Native.GetOriginSpatialCoordinateSystem () [0x00000] in <00000000000000000000000000000000>:0
3.   at UnityEngine.XR.WindowsMR.WindowsMREnvironment.get_OriginSpatialCoordinateSystem () [0x00000] in <00000000000000000000000000000000>:0

Can't debug.

What can I do? Out of ideas.

 

What version of WMR XR Plugin are you using?

 

Windows XR Plugin
Unity Technologies
Version 4.4.2 - March 31, 2021

 

Yes, I will have to do it later this evening or tomorrow AM (GMT -4).

 

I can not reproduce the issue. Let's table this.

I updated to 2020.3.9f1 with WMR XR 4.5.0. I cannot find a build configuration / workflow that leads to the missing DLL. I cannot say if this is a consequence of that update.

It's possible that the original was some transient build/deploy issue. At the time the issues were occurring, I was under significant stress and rather hand-wavily installing and uninstalling packages, switching builds around, and throwing various debugging tools at it. Anything could have happened.

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As a note, though -- possibly (probably) a red herring -- I *have* noticed random sets of build and deploy issues all around strongly correlated with the act of closing or opening an MSVC instance while Unity or another MSVC instance has a build/deploy in progress. I believe the original issue involved this action, and I've seen other random things, e.g. app manifest parse errors on Build & Run to remote device from within Unity, random build failures, etc.

Unsure if that's significant, but just putting it out there.

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In any case, I am satisfied to call this a temporary system configuration issue, or user error, for now. I will post back here if I ever run into this issue again, hopefully with better info on reproducibility.

I don't know what the etiquette is around here but I am changing the title prefix to "Resolved" for the time being.

 

Unfortunately, I've since deleted the build folder that existed when the issues were occurring. Currently (with the other comment I just posted in mind), I can confirm that that DLL is present, for all combinations of build settings that I tried.

Appreciate your prompt replies.