Open PTC04 automation refnum error：2147024703

[Albertfg]

hello everyone, it's my first time to use labview control PTC04, but I got an error as below.

I tried using  demo (excel demo, labview demo fails )from Melexis CD. and Melexis programming Tools .

both can connect to sensor 90316 , read and write successfully.

but always fails with labview.

I even try to register PTC04PSF.dll,MLX90316PSF.dll manually , but still fails.

I programmed with labview 2019, win10,64 bit.

 Please help me how can solve this problem.

Thank you  in advance!

[ecande]

Did you solve your issue?

I am experiencing the same automation refnum error：2147024703 on an old Windows XP machine running activex exe created in VB6 and trying to open it using LabVIEW 7.x

Any insight will be appreciated, thanks.

[CraigA]

I ran into this issue as well. In my case, it was caused by trying to call a 32bit DLL from a 64bit program, which isn't allowed in windows.

Sources:

https://knowledge.ni.com/KnowledgeArticleDetails?id=kA00Z000000PA7SSAW&l=en-US

https://learn.microsoft.com/en-us/windows/win32/winprog64/process-interoperability

The solution is to wrap the 32bit DLL with a 32bit wrapper, then talk to that wrapper over TCP or similar from your 64bit application. It's not ideal, but it's arguably better than regressing your application to 32bit just to cater to an outdated DLL.

As of 2025-09-18T23:12Z Melexis doesn't ship 64bit DLLs, as confirmed by their customer support.