DLLs compiled in 32-bit vs 64-bit environment

[TurboPhil]

I have a VI that uses the Call Library Function Node to call a DLL compiled from C++ code. Another developer wrote and compiled the code on a 32-bit Windows XP machine, and was able to call the DLL in LabVIEW without errors. However, when I ran the VI on my 64-bit Windows 7 machine (although still running 32-bit LabVIEW), it would throw Error 42 (the dreaded "generic error").

Later, I tried compiling the DLL on my 64-bit machine, and the errors went away.

Is that behavior to be expected? That is, should it matter where the DLL was compiled, even if it is called as 32-bit in either case?

Running LV 8.6.1 on both systems.

C++ code compiled in Bloodshed Dev C++

[Starla_T.]

Hi TurboPhil,

Have you tried using the 32 bit dll on a different 32 bit computer than the original development PC?  In theory, a 32 bit dll should be able to run in LabVIEW 32 bit even if it is on a 64 bit machine.   I would be interested to see if you could replicate this issue.   If so, would you mind posting the dll?

Best Regards,

Starla T.