Merge pull request #13592 from ghogen/msbuild-errors-feb-2025

JamesJBarnett · web-flow · commit 0b411e4e1605 · 2025-02-13T13:41:07.000-07:00
Add details for MSBuild errors
diff --git a/docs/msbuild/errors/msb3106.md b/docs/msbuild/errors/msb3106.md
@@ -1,7 +1,7 @@
 ---
 title: "MSB3106 diagnostic code"
-description: "Assembly strong name 'value' is either a path which could not be found or it is a full assembly name which is badly formed. If it is a full assembly name it may contain characters that need to be escaped with backslash(\\). Those characters are Equals(=), Comma(,), Quote('), Apostrophe('), Backslash(\\)."
-ms.date: 12/06/2024
+description: Learn about the possible causes of MSB3106 build error and get troubleshooting tips to resolve it.
+ms.date: 2/06/2025
 ms.topic: "error-reference"
 f1_keywords:
  - MSB3106
@@ -26,14 +26,17 @@ This article describes the MSB3106 error code.
 
 ## Message text
 
-```output
-MSB3106: Assembly strong name 'value' is either a path which could not be found or it is a full assembly name which is badly formed. If it is a full assembly name it may contain characters that need to be escaped with backslash(\). Those characters are Equals(=), Comma(,), Quote('), Apostrophe('), Backslash(\).
-```
+`MSB3106: Assembly strong name 'assembly name' is either a path which could not be found or it is a full assembly name which is badly formed. If it is a full assembly name it may contain characters that need to be escaped with backslash(\). Those characters are Equals(=), Comma(,), Quote('), Apostrophe('), Backslash(\).`
 
 <!-- :::editable-content name="postOutputDescription"::: -->
-<!--
-{StrBegin="MSB3106: "}
--->
+## Remarks
+
+This error occurs when you have a `Reference` element with a path or assembly name, but the assembly couldn't be found with that path or name.
+
+## Resolution
+
+Check the assembly name in the `Reference` element for typos, and make sure it's valid with proper escaping, as the error text indicates.
+
 <!-- :::editable-content-end::: -->
 <!-- :::ErrorDefinitionDescription-end::: -->
 
diff --git a/docs/msbuild/errors/msb3246.md b/docs/msbuild/errors/msb3246.md
@@ -1,7 +1,7 @@
 ---
 title: "MSB3246 diagnostic code"
 description: "Resolved file has a bad image, no metadata, or is otherwise inaccessible."
-ms.date: 12/06/2024
+ms.date: 2/6/2025
 ms.topic: "error-reference"
 f1_keywords:
  - MSB3246
@@ -31,9 +31,17 @@ MSB3246: Resolved file has a bad image, no metadata, or is otherwise inaccessibl
 ```
 
 <!-- :::editable-content name="postOutputDescription"::: -->
-<!--
-{StrBegin="MSB3246: "}
--->
+## Remarks
+
+This error occurs when MSBuild finds an assembly file, but couldn't open the file to inspect the metadata as a .NET assembly. This could be because the file is corrupted so it's not readable as an assembly, or it isn't actually an assembly file.
+
+See [Troubleshoot assembly references](../troubleshoot-assembly-references.md) to investigate the issue, including identifying the specific file MSBuild was trying to read.
+
+If the assembly is part of an SDK or tool, try reinstalling the SDK or tool.
+
+Is the assembly obfuscated? Check the documentation for the obfuscation tool to determine how to obfuscate an assembly that is used as a reference.
+
+If it's your own assembly, try rebuilding it, and try opening the assembly in an assembly viewer such as [ILDasm.exe](/dotnet/framework/tools/ildasm-exe-il-disassembler) to see if it loads correctly.
 <!-- :::editable-content-end::: -->
 <!-- :::ErrorDefinitionDescription-end::: -->
 
diff --git a/docs/msbuild/errors/msb3247.md b/docs/msbuild/errors/msb3247.md
@@ -1,7 +1,7 @@
 ---
 title: "MSB3247 diagnostic code"
 description: "Found conflicts between different versions of the same dependent assembly. In Visual Studio, double-click this warning (or select it and press Enter) to fix the conflicts; otherwise, add the following binding redirects to the 'runtime' node in the application configuration file:"
-ms.date: 12/06/2024
+ms.date: 2/6/2025
 ms.topic: "error-reference"
 f1_keywords:
  - MSB3247
@@ -31,9 +31,38 @@ MSB3247: Found conflicts between different versions of the same dependent assemb
 ```
 
 <!-- :::editable-content name="postOutputDescription"::: -->
-<!--
-{StrBegin="MSB3247: "}
--->
+
+## Remarks
+
+This error occurs when building .NET Framework projects. It is generated by the `ResolveAssemblyReference` task. There are two modes that `ResolveAssemblyReference` can run in, either it can be configured to generate binding redirects, or not. If not set, this error occurs when a conflict occurs between two different assembly versions of dependent assembly.
+
+## Resolution
+
+Consider the following solutions:
+
+### Solution 1: Configure MSBuild to automatically generate binding redirects
+
+Check the property `AutoGenerateBindingRedirects`, which configures `ResolveAssemblyReference` to generate the redirects automatically. You can set this property in Visual Studio. Open **Project Properties** (<kbd>Alt</kbd>+<kbd>Enter</kbd>), open the **Application** tab, and select the checkbox **Auto-generate binding redirects**.
+
+Or, to generate binding redirects automatically by editing the project file, add the following property in one of the `PropertyGroup` elements in the project file:
+
+`<AutoGenerateBindingRedirects>true</AutoGenerateBindingRedirects>`
+
+See [Enable and disable automatic binding redirection](/dotnet/framework/configure-apps/how-to-enable-and-disable-automatic-binding-redirection).
+
+### Solution 2: Add binding redirects to the `app.config` or `web.config` file
+
+You can add the binding redirects manually in the configuration file (such as`app.config` or `web.config`) as suggested in the warning output text. This option is appropriate if you choose not to allow MSBuild to generate the binding redirects automatically, perhaps because you want them explicitly listed in the configuration files to reduce ambiguity.
+
+If you choose not to generate binding redirects automatically, update the `app.config` file (or `web.config`) to add the binding redirects explicitly. The warning message provides the XML for the binding redirects that you can copy and paste into the `runtime` element of the `app.config` file.
+
+Alternately, MSBuild writes binding redirects to an output file if the property `GenerateBindingRedirectsOutputType` is true. It's automatically set to true in the .NET Framework build for executable output files, but you can also set it to true manually for `.dll` output. When MSBuild generates the binding redirects, it adds them to a `.config` file in the output directory, which also contains any binding redirects found in the `app.config` or `web.config` file. You can copy the binding redirects from there and paste the XML into an `app.config` file under the `runtime` element if you want them to be explicitly visible there, or if you don't want MSBuild to generate them automatically.
+
+See [Troubleshooting assembly references](../troubleshoot-assembly-references.md).
+
+## Related content
+
+- [Redirecting assembly versions](/dotnet/framework/configure-apps/redirect-assembly-versions)
 <!-- :::editable-content-end::: -->
 <!-- :::ErrorDefinitionDescription-end::: -->
 
diff --git a/docs/msbuild/errors/msb4036.md b/docs/msbuild/errors/msb4036.md
@@ -1,7 +1,7 @@
 ---
 title: "MSB4036 diagnostic code"
-description: "The 'value' task was not found. Check the following: 1.) The name of the task in the project file is the same as the name of the task class. 2.) The task class is 'public' and implements the Microsoft.Build.Framework.ITask interface. 3.) The task is correctly declared with <UsingTask> in the project file, or in the *.tasks files located in the 'value' directory."
-ms.date: 12/06/2024
+description: Learn about the possible causes of MSB4036 build error and get troubleshooting tips to resolve it.
+ms.date: 2/6/2025
 ms.topic: "error-reference"
 f1_keywords:
  - MSB4036
@@ -26,14 +26,17 @@ This article describes the MSB4036 error code.
 
 ## Message text
 
-```output
-MSB4036: The 'value' task was not found. Check the following: 1.) The name of the task in the project file is the same as the name of the task class. 2.) The task class is 'public' and implements the Microsoft.Build.Framework.ITask interface. 3.) The task is correctly declared with <UsingTask> in the project file, or in the *.tasks files located in the 'value' directory.
-```
+`MSB4036: The 'value' task was not found. Check the following: 1.) The name of the task in the project file is the same as the name of the task class. 2.) The task class is 'public' and implements the Microsoft.Build.Framework.ITask interface. 3.) The task is correctly declared with <UsingTask> in the project file, or in the *.tasks files located in the 'value' directory.`
 
 <!-- :::editable-content name="postOutputDescription"::: -->
-<!--
-{StrBegin="MSB4036: "}LOCALIZATION: <UsingTask> and "*.tasks" should not be localized.
--->
+## Remarks
+
+This error occurs when MSBuild is trying to load a task, but it couldn't find it, or what it found could not be loaded as a task. The task name is given in the error message. Using the name of the task, try to determine whether the task is one of yours, or a system task. Check the task name as referenced in the `UsingTask` element, and make sure it's correct. See [Configure targets and tasks](../how-to-configure-targets-and-tasks.md#usingtask-attributes-and-task-parameters)
+
+If the task is one you're developing, make sure the task class is `public` as suggested, and implements <xref:Microsoft.Build.Framework.ITask?displayProperty=fullName>. Also, make sure the task and its transitive dependencies are loadable.  For .NET Core, you can check the .NET assembly load logging. See [How to use and debug assembly unloadability in .NET](/dotnet/standard/assembly/unloadability). For a .NET Framework task, you can do this by viewing [Fusion log](/dotnet/framework/tools/fuslogvw-exe-assembly-binding-log-viewer).
+
+If the task isn't your own custom task, there might be a corruption problem with the installation of MSBuild, .NET SDK, or Visual Studio. Reinstalling these tools might solve the problem.
+
 <!-- :::editable-content-end::: -->
 <!-- :::ErrorDefinitionDescription-end::: -->
 
diff --git a/docs/msbuild/errors/msb4041.md b/docs/msbuild/errors/msb4041.md
@@ -1,7 +1,7 @@
 ---
 title: "MSB4041 diagnostic code"
 description: "The default XML namespace of the project must be the MSBuild XML namespace or no namespace. If the project is authored in the MSBuild 2003 format, please add xmlns='value' to the <Project> element. If the project has been authored in the old 1.0 or 1.2 format, please convert it to MSBuild 2003 format."
-ms.date: 12/06/2024
+ms.date: 2/6/2025
 ms.topic: "error-reference"
 f1_keywords:
  - MSB4041
@@ -26,15 +26,17 @@ This article describes the MSB4041 error code.
 
 ## Message text
 
-```output
-MSB4041: The default XML namespace of the project must be the MSBuild XML namespace or no namespace. If the project is authored in the MSBuild 2003 format, please add xmlns='value' to the <Project> element. If the project has been authored in the old 1.0 or 1.2 format, please convert it to MSBuild 2003 format.
-```
+`MSB4041: The default XML namespace of the project must be the MSBuild XML namespace or no namespace. If the project is authored in the MSBuild 2003 format, please add xmlns='value' to the <Project> element. If the project has been authored in the old 1.0 or 1.2 format, please convert it to MSBuild 2003 format.`
 
 <!-- :::editable-content name="postOutputDescription"::: -->
-<!--
-{StrBegin="MSB4041: "}UE: This is a Beta 1 message only.
-      LOCALIZATION: <Project>, "MSBuild" and "xmlns" should not be localized.
--->
+## Remarks
+
+This error is caused by an incorrect `xmlns` value in a project file. The `xmlns` attribute appears in older project files; it's no longer required. However, if it's present, it must be exactly as follows:
+
+`xmlns="http://schemas.microsoft.com/developer/msbuild/2003'`
+
+Try deleting the `xmlns` attribute. Since the attribute is no longer required, deleting it should solve this issue.
+
 <!-- :::editable-content-end::: -->
 <!-- :::ErrorDefinitionDescription-end::: -->
 
diff --git a/docs/msbuild/errors/msb4216.md b/docs/msbuild/errors/msb4216.md
@@ -1,7 +1,7 @@
 ---
 title: "MSB4216 diagnostic code"
-description: "Could not run the 'value' task because MSBuild could not create or connect to a task host with runtime 'value' and architecture 'value'.  Please ensure that (1) the requested runtime and/or architecture are available on the machine, and (2) that the required executable 'value' exists and can be run."
-ms.date: 12/06/2024
+description: Learn about the possible causes of MSB4216 build error and get troubleshooting tips to resolve it.
+ms.date: 2/6/2025
 ms.topic: "error-reference"
 f1_keywords:
  - MSB4216
@@ -26,14 +26,19 @@ This article describes the MSB4216 error code.
 
 ## Message text
 
-```output
-MSB4216: Could not run the 'value' task because MSBuild could not create or connect to a task host with runtime 'value' and architecture 'value'.  Please ensure that (1) the requested runtime and/or architecture are available on the machine, and (2) that the required executable 'value' exists and can be run.
-```
+`MSB4216: Could not run the 'taskname' task because MSBuild could not create or connect to a task host with runtime 'runtime' and architecture 'architecture'.  Please ensure that (1) the requested runtime and/or architecture are available on the machine, and (2) that the required executable 'value' exists and can be run.`
 
 <!-- :::editable-content name="postOutputDescription"::: -->
-<!--
-{StrBegin="MSB4216: "}
--->
+## Remarks
+
+Some tasks must run out of the MSBuild process. For example, the task assembly might not match the bitness (32-bit or 64-bit) of the MSBuild process. For such tasks, a process called the task host is launched to run the task. However, there are some limitations. For example, the command `dotnet build` can't launch a .NET Framework process as a task host. Whenever MSBuild can't create a task host, this error occurs.
+
+The issue could be caused by a mismatch in tools. If the task is a system task, try repairing the installation or reinstalling the tools or SDK. For Visual Studio installations, see [Repair Visual Studio](../../install/repair-visual-studio.md). If you don't have Visual Studio installed, reinstall [MSBuild](../walkthrough-using-msbuild.md#install-msbuild), or if you're using `dotnet build`, reinstall the [.NET SDK](https://dotnet.microsoft.com/download).
+
+Check the `UsingTask` element for the task named in the error message for any typos or incorrect paths. See [Configure targets and tasks](../how-to-configure-targets-and-tasks.md#usingtask-attributes-and-task-parameters).
+
+If the task is a custom task, you might need to locate a different binary of the same task that matches your MSBuild or .NET SDK installation. If you have source code for the custom task and you're building it yourself, check the build configuration and make sure you're building the correct type of binary (32-bit or 64-bit), and the architecture is correct for the build environment.
+
 <!-- :::editable-content-end::: -->
 <!-- :::ErrorDefinitionDescription-end::: -->
 
diff --git a/docs/msbuild/errors/msb4278.md b/docs/msbuild/errors/msb4278.md
@@ -1,7 +1,7 @@
 ---
 title: "MSB4278 diagnostic code"
-description: "The imported file 'value' does not exist and appears to be part of a Visual Studio component. This file may require MSBuild.exe in order to be imported successfully, and so may fail to build in the dotnet CLI."
-ms.date: 12/06/2024
+description: "The imported file 'filename' does not exist and appears to be part of a Visual Studio component. This file may require MSBuild.exe in order to be imported successfully, and so may fail to build in the dotnet CLI."
+ms.date: 2/6/2025
 ms.topic: "error-reference"
 f1_keywords:
  - MSB4278
@@ -31,9 +31,16 @@ MSB4278: The imported file 'value' does not exist and appears to be part of a Vi
 ```
 
 <!-- :::editable-content name="postOutputDescription"::: -->
-<!--
-{StrBegin="MSB4278: "}LOCALIZATION: <Import> should not be localized.
--->
+## Remarks
+
+This error occurs when you're using `dotnet build` and trying to import a file, but the imported file requires Visual Studio build files, which `dotnet build` doesn't have access to. For example, this occurs when you try to build an older project that isn't an SDK-style project (it doesn't have the `Sdk` attribute on the `Project` element) with `dotnet build`. The `dotnet build` command can only build SDK-style projects. See [Use MSBuild project SDKs](../how-to-use-project-sdk.md).
+
+This error can also occur if you try to build a C++ project (`.vcxproj`) with `dotnet build`.
+
+## Resolution
+
+Use `MSBuild.exe` or Visual Studio to build the project. Check that Visual Studio is installed on the build machine, and that you have the **.NET Desktop development** workload installed.
+
 <!-- :::editable-content-end::: -->
 <!-- :::ErrorDefinitionDescription-end::: -->
 
