VS 2010 Deployed 64 bit application takes long time to load function, but only the first call

I have an application that calls my GetCSVData method of an object. When I'm running on my development machine the time between calling this function and entering the function is negligible. However, when I compile it as a 64 bit application and execute the code on a client machine, it takes 67 seconds just to go into the function. My development machine is only 32 bit, so I cannot test this out in a 64 bit development mode. I have something like this set up <pseudocode>:

Function A
blah blah blah
msgbox("Calling GETCSVData")
object.GetCSVData(...)
blah blah blah
End Function A

Then in the Object definition
Public Sub GetCSVData(...)
Msgbox("Starting GetCSVData")
...rest of code...

The first time I call this from within the code as a result of a button click, it takes 67 seconds between the two message boxes. There are no other threads running at this point that I control. The next time(s), it is instantaneous, even if called from another instantiation of object. I'm going to try to put a thread running in the background on startup just to call this function, but I would love to know how to fix it properly. Any thoughts are welcome. Thanks in advance.

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