registering .net assembly as com - com

I have a C# class library which calls a native code DLL. I am trying to call this code from VBA.
I configured MSVC to register the generated DL and it works fine. I can access objects in DLL and work with them without any problem.
I want to register them in another computer and I am using the following command:
%windir%\Microsoft.NET\Framework\v4.0.30319\RegAsm.exe /tlb /v MyNetAssembly.DLL
The command return successfully but when I am trying to use the dll objects in VBA, I am getting error file not found (80070002). I tried to add path to the place that dll resides, copy the dlls to windows directory, using /codebase option, without any success.
What is the problem and how can I solve it?

Related

Cannot find the reference specified-Visual Basic 2013

I've got a new system. I am trying to connect to and run the system through a 64-bit Windows 7 PC. The company sent me a Visual Basic project for that. It uses .NET framework 4 and Windows Form Applications. The target CPU is x86.
In the References tab, next to three of the COM references there are "The system cannot find the reference specified" statements. When built, the project gives the namespace errors and warnings because of these objects. The other references work fine. I've then seen those .dll files in the debug folder. I think they are generated by the company before sending me. They also exist in the bin\debug folder.
I've removed the three from the references list in the project and tried the following separately:
1) In the project, refer to the .dll files that exist in the debug folder. (Seems a fake way, but removes all the errors when the project is built. When debug, it gives the "Retrieving the COM class factory for component with CLSID ... failed due to the following error: 80040154" error.)
2) Copy the .dll files in the debug folder to C:\Windows\SysWOW64 folder, then register through regsvr32 "name.dll" in the console as admin. This way, I get the ".dll was loaded, but the DllRegisterServer entry point was not found" error. (In the regedit window, the registry editor cannot find the ID's of those references that are seen in the project properties in VB.)
3) Do the item (2), but with the C:\Windows\System32 folder instead of SysWOW64. The same error when registering.
4) Changed the solution platform to x86 and tried the items 1,2, and 3. Still the same errors.
Do I have to register these dll files? And, am I supposed to register exactly these dll files that exist in the debug folder? Or are they supposed to be generated after build by referring to some 'missing' type libraries in the references tab? I don't have these type libraries, though.
All suggestions are welcome ASAP. Thanks in advance.
You have three Interop dlls for your project, correct? These dlls just allow you to use a COM dll without having to talk directly to the COM dlls yourself.
Referencing the dlls in the bin/Debug directory should be fine, since those are probably the correct dlls that the project was built with. However, you will want to move them to another folder before continuing.
What you need to get from the company that sent you the project is the original COM dlls and their dependencies, if any. Usually an interop dll is called Microsoft.Phone.Interop.dll where it is performing interop with Microsoft.Phone.dll. Microsoft.Phone.dll needs to be registered on your computer using regsvr32 and then you just need a reference to the interop dll.

Reference VB.NET DLL in Kofax Document Validation Script

We are working on a validation script for Kofax Capture 9.0 / 10.0 in VB.NET 3.5.
We know how to create a script using the Admin Module, and how to get it operational.
The problem is that we need to reference a dll, located on a remote machine. (GAC is no option) This dll holds abstract classes we need in each validation script.
Even when putting the dlls locally (copy local), the Validation Module (index.exe) immediately throws the "cannot find reference" exception, even though the project compiled perfectly.
I guess the basic question comes down to: where do we put the dlls, in order for the Validation Module to find them?
The simple answer is to put the dll in the same folder as the application because this is one of the places which .NET will probe when trying to find it. The Validation module is run from the Capture bin directory which will be something like "C:\Program Files (x86)\Kofax\CaptureSS\ServLib\Bin\". This would need to be done on each client using Validation.
If you have a more complicated scenario, you could look implementing the AppDomain.AssemblyResolve Event and using Assembly.LoadFile to get the assembly from a custom location, but the using the bin path is less complicated.
If you end up having further trouble, you can troubleshoot by using the Assembly Binding Log Viewer (Fuslogvw.exe) which can tell you more details about why the assembly failed to load and where .NET tried to search for it. Assembly loading can fail for reasons other than just the path.
For more detail on how .NET loads assemblies, see the following:
How the Runtime Locates Assemblies
Locating the Assembly through Codebases or Probing
We found a solution: add all library files as "links" to the project. (Add --> Existing File --> small arrow next to "Add" --> Add as Link)
This ensures the files are compiled when you build the project. The Kofax Validation Module can now find the files, whereas when referencing the file, it could not. Why it could not, remains a mystery...

Use function of DLL in VBScript

I want to use a function of my Encryption.dll in my VBScript.
If I try to register the dll with regsvr32 /i Encryption.dll I get the error that the dll is loaded, but he can't register the file because there is no DllRegistryServer-Entrypoint.
So I tried another way as I read in a forum:
Set yourClass = CreateObject("Encryption.Hashing")
There I'm getting a ActiveX error.
Anymore ideas of what I can do?
Sounds like maybe the DLL was compiled improperly? Do you have the source? If not, try something like Telerik's JustDecompile and see if it can decompile it. This is not the end all be all kind of test but if it's a .NET dll, you should be able to decompile it. If it's a native DLL, there should be an error.
Without knowing that, there's several reasons you could be having problems.
Try creating a wrapper that exports the functions you need; test it in VS and then build it and try installing it again. Oh, one more thing. Native Libs have a .lib file that usually comes with the DLL if it's meant to be linked to for invoking purposes. That .lib and it's corresponding header files will be what you need to write a wrapper. Cheers.

COM access to VB.Net dll without strong name signing

I'm converting a VB6 dll to VB.Net using Visual Studio 2008 Express. I want to use the same .dll to integrate with Excel via Excel-DNA, but also to be available via COM (I need to be able to call it from VBScript and VBA).
If I leave the assembly unsigned, I have access to all of the ExcelDNA functionality but no COM access.
If I sign the assembly with a strong name, then when I try to build the .dll I get the following error:
Unable to emit assembly: Referenced assembly 'ExcelDna.Integration' does not have a strong name
What are my options?
You don't have to strong-name a [ComVisible] assembly. It is only required when you want to install it in the GAC. Not strictly necessary although not a bad idea to fight DLL Hell. You need to register it with Regasm.exe using the /codebase option. Visual Studio already does that automatically, although the option might be missing in the Express edition.
Fixing the second problem shouldn't be hard either. Just rebuild the Excel-DNA solution from the source code you can download from Codeplex.
Excel-DNA has an option to expose your .NET classes to COM directly, so you can use them directly from VBA as regular COM classes.
To do this your class must be ComVisible (or the whole assembly must be ComVisible), and you must mark the ExternalLibrary as ComServer='true' in the .dna file, something like:
<DnaLibrary RuntimeVersion='v4.0' />
<ExternalLibrary Path='MyAddIn.dll' ComServer='true' />
</DnaLibrary>
Then you have some options for registration:
either call "Regsvr32.exe MyAddInDna.xll"
or in the AutoOpen of your add-in, call ExcelDna.Integration.ComServer.RegisterServer()
Both of these set the registry entries so that the .xll file becomes the COM server for your classes. You can then access them late-bound from VBA, with CreateObject("MyNameSpace.MyClass").
You need another step to set up a type library (to give you intellisense in VBA). For this you generate the type library with tlbexp.exe. The regsvr32 / ComServer.RegisterServer call will find the type library and register it too.
You can also pack the .dll into your .xll file (adding a pack='true' attribute to the ExternalLibrary tag) and the type library will also be packed if present, and registered from the resource in the .xll file when you call Regsvr32.exe
So the end result could be a single file .xll add-in that is both an Excel Add-In with UDFs, ribbons, RTD servers and also a COM server that you can access from VBA.
More info in the discussions here: http://exceldna.codeplex.com/discussions/252721 and here: http://groups.google.com/group/exceldna/browse_frm/thread/4c5a71efbe96d885.

Using tlbexp.exe on a COM dll

I am trying to set up communication between Centura and a COM .dll. (Downloaded from http://download.resip.fr for a database import)
Centura requires a .tlb file to be able to communicate to this component. Normally I would use regasm /tlb to generate the .tlb but seeing as it is a COM .dll this is not possible.
I found that I could use tlbexp for .NET dll's: http://msdn.microsoft.com/en-us/library/hfzzah2c(v=vs.80).aspx
I tried this out, knowing it would probably fail (as I have COM .dll). I received this error:
TlbExp : error TX0000 : Could not load file or assembly 'file:///C:\Windows\system32\ResipBcb.dll' or one of its dependencies. The module was expected to contain an assembly manifest.
Using Dependency Walker I noticed two .dll's missing. I found ieshims.dll online but I can't find the wer.dll. See this question.
I don't know if the tlbexp failure has anything to do with this file that is missing?
To sum up, my question is:
How do I get a .tlb from this .dll? I can't seem to find any way to extract the .tlb out of this COM .dll.
Best regards
Clint Cambier
What you are trying to do only works for .NET assemblies, not native COM servers. The type library for them is almost always embedded inside the DLL. In Visual Studio, use File + Open + File and select the DLL. Open the "TYPELIB" node, right-click the resource (usually 1), Export. Save it to, say, a project directory, use the .tlb filename extension.
TblExp and regasm are only valid on .NET assemblies, what you have is most likely a standard non .NET COM DLL. So neither of those two commands are valid on this DLL.
Standard COM objects are registered using regsvr32. Try running that against your DLL and see if it registers correctly. If it does you should see it listed in Centura's ActiveX explorer.