It seems that you have referenced several projects into your main project.
As a suggestion, you should make every project’s Configuration is x64 and Configuration is Debug.
In other words, you have to ensure that the same Configuration and Platform of your main project has been already be built with on every referenced project.
My first thought is that your referenced project does not build with Debug and did not keep the same configuration and platform with the main project. So your main project with Debug|x64 cannot find the corresponding output files Debug|x64(which means that your referenced projects do not have such folder), so the issue occurs.
In my memory, the dll of the refenced project can only be used when the Configuration and Platform is the same of the main project. If they are not the same, they cannot be used forever. And you make sure that the referenced projects have the same output folder as the main project.
For an example, if you built your Reconciler project with Debug|x64, you should ensure the referenced projects has the output folder with Debug|x64 mode.
And if it does not help, please follow the below suggestions:
Suggestions
1) close VS, delete .vs under every solution folder, bin and obj folder of every project.
2) open every referenced project–>build the project with Debug|x64 mode.
3) When you finish it, reopen your Reconciler project and you can not see such issue with Debug|x64.
Besides, if your referenced projects are lib projects, you can directly referenc the dll rather than the project.
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