"resource not found" when calling ibrary node

[ManifestMind]

I have an OL 490 from Optronic Laboratories that I am trying to write labview code for so that I can automate it.  It is connected to my computer through a USB, and it came with software that I can use to control it with ease.  It also came with a software development kit, which includes a .dll file.  I also have a list of the Command Set, and it has commands listed and how to use them, such as:

long ConnectToOL490()

Returns : 0 - Failed, OL490 not connected
                1 - Success

I think I have to use the Call Library Function Node vi to do this.  However, when I try, I always get an error:

Error 15 occurred at Call Library Function Node in Untitled 1

Possible reason(s):

LabVIEW:  Resource not found.
=========================
NI-488:  Serial poll byte queue overflow.

What is the deal, and what does this error mean?  If I change the path of the .dll file to a different .dll file, I still get the same error, so this leads me to believe that the 'resource' that this error is referring to is the function (ie. it can't find the function in the .dll).  Why would that happen?

Thanks!

[ManifestMind]

Note:

I just realized that I think the functions are written in Visual C#.  As I am pretty sure that Call Library Node will not work unless the function is written in C, I will work on trying to figure out how to call a Visual C# function.

Any help will still be greatly appreciated in this endeavor.

[smercurio_fc]

Visual C# creates .NET assemblies. You will need to use the .NET functions to access that library. See the LabVIEW Help on using the .NET functions.

[fra6]

Did you solve the issue with the OL 490? I would be very glad to have your vi. Thanks