>What is usually the trouble when a .dll cannot load when calling a function and there was no entry point error in the declaration statement? Using ver.dll...

There are a number of possible causes; the most frequent one is that some other resource required by the .DLL is not present/cannot be found. Commonly, this might mean that some shared .DLL is not there, or not current, or that if it is there, that it has not been registered yet.

Other things include declaring the wrong number of parameters in the DECLARE, or the right number of parameters, but the parameters are of the wrong type expected by the .DLL.