Could not load file or Assembly

Ramco Ramco

I am getting below error -

Could not load file or assembly 'WebApp' or one of its dependencies. An attempt was made to load a program with an incorrect format.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.BadImageFormatException: Could not load file or assembly 'WebApp' or one of its dependencies. An attempt was made to load a program with an incorrect format.

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Thanks

4 Replies

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Subarta Ray2y ago
Hi Ramco ,

The error "System.BadImageFormatException" suggests a mismatch in the architecture (32-bit/64-bit) between your application and dependencies. Confirm your IIS application pool uses the correct .NET framework version and matches your project's platform target (x86 or x64). Check referenced DLLs for compatibility. If using IIS Express, verify its configuration in applicationhost.config. Rebuild your solution, and consider using the corflags tool for advanced troubleshooting. Ensure native dependencies align with your chosen architecture. Review the full stack trace for specific details on the problematic assembly.
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Uttam Chaturvedi2y ago
Please be more clear with your questions for example in what scanarios you are facing this issue.

It would be good you can paste piece of code, so that people can give you exact solution.
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Satyaprakash Samantaray2y ago
If you are facing issue in Visual studio while run application:
- Check your WebApp.dll is there in reference folder on not if u are trying to access WebApp by Using system namepace.
- You can that WebApp.dll in your project and it will work.
If you are facing issue in IIS after deployment:
- http://surl.li/oncsp
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Jayraj Chhaya2y ago
The "Could not load file or assembly" error typically occurs when there is a mismatch between the architecture of the application and the referenced assembly. This can happen if the application is built for a different platform (e.g., x86) than the referenced assembly (e.g., x64).

To troubleshoot this issue, follow these steps:
1. Check the architecture of your application: Ensure that the target platform of your application matches the architecture of the referenced assembly. You can do this by right-clicking on your project in Visual Studio, selecting "Properties," and navigating to the "Build" tab. Verify that the "Platform target" is set correctly.
2. Check the architecture of the referenced assembly: Verify that the referenced assembly is built for the same platform as your application. If not, you may need to obtain a version of the assembly that matches your application's architecture.
3. Check for any missing dependencies: The error message mentions that the issue could be related to one of the dependencies of the 'WebApp' assembly. Ensure that all the required dependencies are present and properly referenced in your project.
4. Clean and rebuild your solution: Sometimes, the error can be caused by a corrupted build. Clean your solution and rebuild it to ensure that all the necessary files are generated correctly.
5. Check the version compatibility: Ensure that the version of the referenced assembly is compatible with your application. If there are any version conflicts, you may need to update or downgrade the assembly to a compatible version.
By following these troubleshooting steps, you should be able to resolve the "Could not load file or assembly" error and successfully run your Dot net application.
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