Unexpected error in the task "DefineStaticWebAssetEndpoints"

[vsfeedback]

This issue has been moved from a ticket on Developer Community.

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[severity:I'm unable to use this version] [regression] [worked-in:17.13.6]
After the last upgrade from 17.13.6 to 17.14.0, my project didn’t compile. This is the error. I rolled back, and it worked again. The problem is with all .css files.

Error inesperado en la tarea "DefineStaticWebAssetEndpoints".
System.AggregateException: Se han producido uno o varios errores. ---> System.InvalidOperationException: Last write time for 'D:\VS\Codigo\WebCore\wwwroot\css\bpmProcesos.css' is not defined.
en Microsoft.AspNetCore.StaticWebAssets.Tasks.StaticWebAsset.Validate()
en Microsoft.AspNetCore.StaticWebAssets.Tasks.StaticWebAsset.FromTaskItem(ITaskItem item)
en Microsoft.AspNetCore.StaticWebAssets.Tasks.DefineStaticWebAssetEndpoints.ParallelWorker.Process(Int32 i, ParallelLoopState _)
en Microsoft.AspNetCore.StaticWebAssets.Tasks.DefineStaticWebAssetEndpoints.<>c.<Execute>b__16_2(Int32 i, ParallelLoopState loop, ParallelWorker state)
en System.Threading.Tasks.Parallel.<>c__DisplayClass17_01.<ForWorker>b__1() en System.Threading.Tasks.Task.InnerInvokeWithArg(Task childTask) en System.Threading.Tasks.Task.<>c__DisplayClass176_0.<ExecuteSelfReplicating>b__0(Object <p0>) --- Fin del seguimiento de la pila de la excepción interna --- en System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions) en System.Threading.Tasks.Task.Wait(Int32 millisecondsTimeout, CancellationToken cancellationToken) en System.Threading.Tasks.Parallel.ForWorker[TLocal](Int32 fromInclusive, Int32 toExclusive, ParallelOptions parallelOptions, Action1 body, Action2 bodyWithState, Func4 bodyWithLocal, Func1 localInit, Action1 localFinally)
en System.Threading.Tasks.Parallel.For[TLocal](Int32 fromInclusive, Int32 toExclusive, Func1 localInit, Func4 body, Action1 localFinally) en Microsoft.AspNetCore.StaticWebAssets.Tasks.DefineStaticWebAssetEndpoints.Execute() en Microsoft.Build.BackEnd.TaskExecutionHost.Execute() en Microsoft.Build.BackEnd.TaskBuilder.<ExecuteInstantiatedTask>d__26.MoveNext() ---> (Nº de excepción interna 0) System.InvalidOperationException: Last write time for 'D:\VS\Codigo\WebCore\wwwroot\css\bpmProcesos.css' is not defined. en Microsoft.AspNetCore.StaticWebAssets.Tasks.StaticWebAsset.Validate() en Microsoft.AspNetCore.StaticWebAssets.Tasks.StaticWebAsset.FromTaskItem(ITaskItem item) en Microsoft.AspNetCore.StaticWebAssets.Tasks.DefineStaticWebAssetEndpoints.ParallelWorker.Process(Int32 i, ParallelLoopState _) en Microsoft.AspNetCore.StaticWebAssets.Tasks.DefineStaticWebAssetEndpoints.<>c.<Execute>b__16_2(Int32 i, ParallelLoopState loop, ParallelWorker state) en System.Threading.Tasks.Parallel.<>c__DisplayClass17_01.<ForWorker>b__1()
en System.Threading.Tasks.Task.InnerInvokeWithArg(Task childTask)
en System.Threading.Tasks.Task.<>c__DisplayClass176_0.<ExecuteSelfReplicating>b__0(Object <p0>)<---

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Original Comments

Alison Jin [MSFT] on 5/20/2025, 00:05 AM:

Thank you for your feedback! Does this reproduce for the specific project? If iso, what kind of project it is (C#/C++ Console App, WinForms, WPF, AspNet, etc…)? Could you please provide a sample solution that has this problem so that we can conduct further research? It would be very helpful if you could provide some screenshots that has this problem or record a video for this scenario by using ScreenToGif.Thanks for your help!

We look forward to hearing from you!

Jorge Garces on 5/20/2025, 08:16 AM:

(private comment, text removed)

Feedback Bot on 5/26/2025, 02:09 AM:

We have directed your feedback to the appropriate engineering team for further evaluation. The team will review the feedback and notify you about the next steps.

[ilonatommy]

The fixing PR should be in sdk: dotnet/sdk#49056.

[javiercn]

This was addressed in 9.0.302