Develop Reference

How do I import my user control dll to my new project?

I have a user control project which contains a few controls I made myself. This project's output type is Class Library which produces a .dll file so I can import that in other projects. My problem here is when I rebuild the .dll project with Any CPU and import that dll to my second project I get this error:
An unhandled exception of type 'System.BadImageFormatException' occurred in SecondProject.exe
Additional information: Could not load file or assembly 'TestUserControlsDLL, Version=1.0.0.0, Culture=neutral, PublicKeyToken=1234567890abcdef' or one of its dependencies. An attempt was made to load a program with an incorrect format.
When I rebuild my dll project in 64bit I can see the user controls in design view but then I can't run my second project by clicking F5. This question is probably asked before but I'm at the point which I don't even know how to search about this problem.
What I try to do is import my dll output (user control project) into another project (which will be 64 bit) and be able to see the controls in design view and also able to run my project.
Problem solved..
I don't know how but creating a new dll project and just copy-paste my controls inside that new project under new namespace solved all of my problems. It's working now

take a look, at both target framework versions. (Project properties)
e.g. if your exe is 4.6.1 and your dll is 4.7.2, you get this error

Use .net DLL with broken References

I have to use a DLL as an API in my application (C#, .NET 4.5). I can reference the DLL normaly. No error at all. But if I want to use any class of this DLL, I get the following compile error:
Error CS1705 Assembly 'Assembly_X' with identity 'Assembly_X,
Version=12.3.0.0, Culture=neutral, PublicKeyToken=c878e80841e75d00'
uses 'Assembly_YY, Version=65535.65535.65535.65535, Culture=neutral,
PublicKeyToken=c878e80841e75d00' which has a higher version than
referenced assembly 'Assembly_YY' with identity 'Assembly_YY,
Version=12.3.0.0, Culture=neutral, PublicKeyToken=c878e80841e75d00'
Then i checked the DLL (Assembly_X) in ILSpy. The Assembly_X has two references to Assembly_YY: One with the version 12.3.0.0 and one with the version 65535.65535.65535.65535.
I tried the "bindingRedirect" in the App.config. But since the error occures during compile time this doesn't help.
I don't have the source code of Assembly_X or Assembly_YY.
How can I use this DLL or repair it?
UPDATE
The developers of the dll finally answered my call for help. The only work around they know of is to use Visual Studio 2013 instead of Visual Studio 2015 or 2017. It seems VS 2013 is not bothered by these double reference at all.
They write, that the error is created by a encrypting tool for the dll.
Thank you all for your ideas and help.

It looks like the first DLL is referencing a library which is a higher version than the other DLL you are using.
so you have 3 DLL's to consider: A, B & Bv2
Your project is referencing A & B
But A references Bv2 (an updated version of B)
SO when you go to use functions of A it throws an error because it finds B instead of Bv2.

The problem basically that you are referencing 'Assembly_X' which references assemblies 'Assembly_YY' versions 12.3.0.0 and 65535.65535.65535.65535 and you referenced only 'Assembly_YY' version 12.3.0.0 in your application and didn't reference 65535.65535.65535.65535
Now according to the problem explanation on Microsoft Docs, and your example which you don't have the source code for the assemblies you have to:
Add a reference to 'Assembly_YY' version 65535.65535.65535.65535 of the DLL to your application to make it compile and to enable the application to run, you can provide an application configuration file that includes a <dependentAssembly> element that uses <assemblyIdentity> and <codeBase> child elements to specify the location of version 12.3.0.0 of the DLL.

You are referencing a higher version of DLL then the one you currently have.
You will need to add the reference to the higher version assembly:
'Assembly_YY, Version=65535.65535.65535.65535, Culture=neutral, PublicKeyToken=c878e80841e75d00'
in order to solve this.
Right now you are referencing
'Assembly_X' with identity 'Assembly_X, Version=12.3.0.0, Culture=neutral, PublicKeyToken=c878e80841e75d0
If this is a downloadable library, search for it in the nuget package manager and download it.
If it's a library written by you, obtain the latest version of the library and add it to your project.

C# Project, GAC, DLL

i'm having a problem with my built Application.
I have a project taken from here modified it and implemented in my program.
Shortly, this TableProc project generates a report to OpenOffice Calc and uses some libraries from OpenOffice - cli_basetypes (GAC/MSIL), cli_oootypes (GAC/MSIL), cli_uno (GAC/MSIL), cli_ure (GAC/MSIL), cli_uretypes (GAC/MSIL) AND cli_cppuhelper (GAC32).
Looks like:
Solution
.....Project1 (references TableProc)
.....Project2 (references TableProc)
.....TableProc (implemented) (references on libraries in bin directory cli_basetypes.dll and others)
So, when i'm in debugging mode VS 2010, those DLL are in directory */bin/ - Everything works fine - reports are done.
But when i build up my application:
1. There are no DLL's for cli_basetypes, cli_oootypes and others
2. There are project1.dll, project2.dll and TableProc.dll and
Program.exe
PROBLEM:
In a built up application, it tells that:
Error 1:
Could not load file or assembly 'cli_cppuhelper, Version=1.0.14.0,
Culture=neutral, PublicKeyToken=ce2cb7e279207b9e' or one of its
dependencies. Ann attempt was made to load a programm with an
incorrect format.)
Ok, I tried to manually put those DLL's next to my Program.exe - same error.
Then I found out, that those libraries are installed in GAC when you install Open Office. I looked at them, and noticed that all of them are installed in GAC/MSIL but cli_cppuhelper is installed in GAC/32.
I tried to manually copy cli_cppuhelper assembly from GAC/32 to GAC/MSIL, and got this error:
Error 2:
Is not a valid Win32 application. (Exception from HRESULT:
0x800700C1))
From this i understood, that my apllication, when looks for DLL's it looks only in GAC/MSIL
Please help, i don't know what to do...

For those that find this in the future.
The problem is that the targeted platform in Visual Studio is incorrect. The .dlls need to be compiled with the correct bit version.
You need to change the targeted platform in Visual Studio to:
64-bit -> x64
32-bit -> x86
Note: AnyCPU does not work.

Change your Platform from AnyCPU to x86.

System.IO.FileNotFoundException error when running Windows Phone 8 application

I have a Windows Runtime Component that uses some native libraries (the PJSIP library). This component is used in a Windows Phone 8 Application and when I try to invoke a function from the native component I get the following error:
An exception of type 'System.IO.FileNotFoundException' occurred in TestingApp.DLL but was not handled in user code
with the Source (at Exception Details) in mscorlib.
Can anyone point out what may be causing this error and how can I find out what is missing actually? When I try to put a breakpoint in my Windows Runtime Component, at runtime, the breakpoint appears as disabled.
Regards,
Tamas

Add the missing dll to the project (like adding a new file) and mark it as content. Then reference the dll from this location. This may resolve your problem.
I guess it is not working as it is not being deployed within your application.

In Visual studio, under the debug menu select 'Exceptions' then in the dialogue that appears enable 'Thrown' for 'Common language runtime exceptions'
Then re-run your application, Visual Studio should break now at the line in the code that is causing the Null Exception.

If you reference a native library, double-check if you also reference C++ Runtime. Under your project in Solution Explorer, right-click References > Add Reference... Go to Extensions and check Visual C++ Runtime Package.

Check the library file you linked, it should be a import library for DLL file.
An import library (.lib) file contains information the linker needs to resolve external references to exported DLL functions, so the system can locate the specified DLL and exported DLL functions at run time.
When app start it find DLL files according to the import library, but there is no such DLL files, so C# throw a FileNotFoundException. Make sure link to a static library

c# app can't find dll in its working directory

I just switched from C++ to C# and I am a bit confused about referencing DLLs.
I have a third party DLL and a simple testing application that uses some of its methods. When I compile the project, everything goes well, but when I run the compiled app on another computer, I've got an error that says that the DLL is missing even though the DLL is in the app's working directory. What's even more strange is that I have access to the source code of another app that is dependent on an older version of this DLL and this app works well.
I've gone through the code and all the solution settings without finding anything really different.
Can you tell me how to reference a .dll from a working dir (Visual Studio 2010)?
Below is the exception:
System.IO.FileNotFoundException was unhandled
Message=Could not load file or assembly 'TIS.Imaging.ICImagingControl32, Version=3.2.4.1146, Culture=neutral, PublicKeyToken=257805929e8b7928' or one of its dependencies. The system cannot find the file specified.
Source=ICtestapp
FileName=TIS.Imaging.ICImagingControl32, Version=3.2.4.1146, Culture=neutral, PublicKeyToken=257805929e8b7928
FusionLog=WRN: Assembly binding logging is turned OFF.
To enable assembly bind failure logging, set the registry value [HKLM\Software\Microsoft\Fusion!EnableLog] (DWORD) to 1.
Note: There is some performance penalty associated with assembly bind failure logging.
To turn this feature off, remove the registry value [HKLM\Software\Microsoft\Fusion!EnableLog].
StackTrace:
at ICtestapp.Form1.InitializeComponent()
at ICtestapp.Form1..ctor()
at ICtestapp.Program.Main()
InnerException:

Here's a good blog post from Suzanne Cook from the .net team on debugging .net loader issues.
http://blogs.msdn.com/b/suzcook/archive/2003/05/29/57120.aspx
and here's the details on how it loads:
http://msdn.microsoft.com/en-us/library/yx7xezcf(v=vs.71).aspx

You have to add the dll as reference in your project references, once you added the library in the reference, when you compile the program the dll will be automatically copied to the compilation output folder unless otherwise specified in the reference properties ...
Then if you copy all items that you will find in the compilation output folder in the new location in the other PC, you should not have any problems.
Check also that the .NET framework installed on the other machine is at least as the same level of the project target ..

This also happens when you copy the debug executables over to another machine. Try compiling in release and moving over.