Hi, I had this problem already last month and thought it was just a fluke, but it happens on every single Android project in my solution. The manual fix is no good because our build system is also experiencing this issue and I can't constantly modify or delete generated files on the build server obj folder, not very fun ..

So any project with <TargetFramework>net8.0-android</TargetFramework> produces this file in the \obj\Debug\net8.0-android\ folder:
__Microsoft.Android.Resource.Designer.cs

The content looks like this:
//------------------------------------------------------------------------------
// <auto-generated>
// This code was generated by a tool. DO NOT EDIT
// </auto-generated>
//------------------------------------------------------------------------------
using System;

namespace nCrunchTemp_9f7051ca-3ab6-4ede-90cc-857520460535 {
#pragma warning disable IDE0002
public partial class Resource : _Microsoft.Android.Resource.Designer.ResourceConstant {
}
#pragma warning restore IDE0002
}

there are not any special resources, just the standard stuff that gets generated from the Android .NET8 csproj template (values\strings.xml and layout\activity_main.xml plus the icons).

The fix is also easy, the above code obviously doesn't compile because the GUID after nCrunchTemp is not a valid namespace name, changing it to anything else works, there is no code here anyway. It also seems to stay fixes as this file is not generated again until some resource changes happen.

Ok, thanks for the quick response, makes sense. Sorry for not being clearer on my initial post, we have our code separated to shared library code, and then for each platform a project that has all the platform specific stuff (mostly just icons, layout and whatever is the startup). All tests and NCrunch relevant things are in their own test project just referencing the shared library code, so we don't care much about the platform specific projects as long as they compile. But this is exactly the issue, once NCrunch generates that extra file in the \obj\ folder the project won't longer compile unless that file is fixed or deleted. I also noticed today after changing it once and then deleting it, it gets generated correctly again.

We already use ignore the whole project, but I guess sometimes it is already loaded and stuff is generated and then causing the issue, not sure why it happened on the build system as the project was supposed to be ignored and looking at the metrics it is not there. For now it works fine, just next time we add an android or ios project it probably will pop up again, not worth the effort to write script, will fix it manually next time again, but would be nice in the future if nCrunch would not generate .Designer.cs files that don't compile.