dll not loading issue

[auma560058]

Hi All,

I am using 2023q3 32bit ,my query is i am using a customized dll for bluetooth connection, which was worked fine till the latest version of .dll was built.

the latest version was not able to load in .net container, the dll was supporting in other 

[altenbach]

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@auma560058 wrote:

Hi All,

I am using 2023q3 32bit ,my query is i am using a customized dll for bluetooth connection, which was worked fine till the latest version of .dll was built.

the latest version was not able to load in .net container, the dll was supporting in other 

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Who built the last dll version and what did they change?

Where exactly is "in other"?

[Kyle97330]

It could be one of a number of problems.  Here's some of them:

1. If the new DLL has a dependency on another DLL, that other DLL could be missing.  Check to see if the DLL requires other non-system support DLLs.  I use a utility called ILSpy but there are others out there.
2. Windows often marks new DLLs as being suspicious and flags them as not being able to run until you manually enable them.  Right-click the DLL and check the file properties in Explorer and see if you need to unblock it.
3. Unlikely, but your DLL needs to support the same bitness as your LabVIEW is.  Many DLLs work for both, and this one obviously worked for you earlier, but since it's an update there's always a chance that whoever made it either dropped 32-bit support or you got the wrong one accidentally.
4. LabVIEW 2023 only supports .NET up to the last version 4 of the framework.  If the DLL was made with .NET Core 5 or .NET standard or something else like that, it won't work.  LabVIEW 2025 has beta support for some of these newer .NET versions though.

[rolfk]

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@Kyle97330 wrote:

LabVIEW 2023 only supports .NET up to the last version 4 of the framework.  If the DLL was made with .NET Core 5 or .NET standard or something else like that, it won't work.  LabVIEW 2025 has beta support for some of these newer .NET versions though.

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That is specifically .Net 8.0. Any other earlier .Net Core version is not officially supported and very likely going to have problems. Also the current support allows calling assembly methods with basic datatypes as parameter. Anything else is still basically not possible.

From the 2025Q1 release notes:

.NET (Core) 8.0 Support

LabVIEW 2025 Q1 supports loading and running .NET 8.0 assemblies on Windows. The following features are also supported with .NET 8:

• Building applications, packed libraries, and source distributions.
• Defining and using static properties and methods.

Note: The .NET Container, registering VIs for event callbacks, and building .NET assemblies, are not yet supported with .NET 8.

LabVIEW 2025 Q3 did fix several problems but did not add additional functionality.