IOException was unhandled - Cannot locate resource app.xaml

Question

In one of my WPF projects I get this error when I open the solution and start it up when debugging it. If I rebuild the solution and start it again, the error goes away.

I have implemented command line support for application by removing the StartUpUri in App.xaml using this:

WPF Command Line

How do I get rid of this annoying error?

Using VS 2010 .net 4.0

enter image description here

System.IO.IOException was unhandled
  Message=Cannot locate resource 'app.xaml'.
  Source=PresentationFramework
  StackTrace:
       at MS.Internal.AppModel.ResourcePart.GetStreamCore(FileMode mode, FileAccess access)
       at System.IO.Packaging.PackagePart.GetStream(FileMode mode, FileAccess access)
       at System.IO.Packaging.PackagePart.GetStream()
       at System.Windows.Application.LoadComponent(Object component, Uri resourceLocator)
       at ESPS3.ServerSchemaUtility.App.InitializeComponent() in e:\ESP3.0\InternalTools\ServerSchemaUtility\ServerSchemaUtility\App.xaml:line 1
       at ESPS3.ServerSchemaUtility.App.Main() in E:\ESP3.0\InternalTools\ServerSchemaUtility\ServerSchemaUtility\obj\x86\Debug\App.g.cs:line 0
       at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
       at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
       at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
       at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Threading.ThreadHelper.ThreadStart()
  InnerException:

I get the error all the time too. Im sick and tired of it. Wondering if you found a fix... — SpoiledTechie.com, Apr 12 '12 at 15:53

score 1 · Accepted Answer · answered Apr 17 '12 at 04:03

I have seen that error before, when porting from VS 2005 to 2008. Never seen in 2010. For some reason, the build settings for app.xaml were lost. So you can check the the properties of app.xaml. The correct settings are shown in the image attached.

app.xaml properties

On the other hand, if you are working with MVVC, it can be a different cause, like explained here: http://social.msdn.microsoft.com/Forums/en-US/wpf/thread/39d7a4dd-9034-4ae8-843c-ccd4940ba51c/

score 1 · Answer 2 · answered Sep 16 '15 at 22:20

1

I have the same situation as specified in question (VS2010).
Yesterday, project worked without problems. Today, with no changes to the code, project reported error.

In my case after Menu -> Build -> Clean Solution project run without error.

answered Sep 16 '15 at 22:20

cypizek

327
2
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score 0 · Answer 3 · answered Mar 01 '19 at 10:19

0

Changing Windows 10 display language from English to German (the app was originally developed on a German system) fixed it for me.

answered Mar 01 '19 at 10:19

Tim Pohlmann

4,140
3
32
61

IOException was unhandled - Cannot locate resource app.xaml

3 Answers3

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