It shows error message when I trying to use DiscoverAll function. I am using desktop Franson dll. The error message showing "Unable to find an entry point named 'Network_SetDiscoverAll' in DLL 'BlueTools.dll'".
You are using an older version of the core dlls.
Make sure you are using the latest BlueTools.dll, BlueToolsMS.dll, BlueToolsWC.dll and BlueToolsWC150.dll.
If you have them copied to the application directory it's possible you are loading the incorrect version as the newer versions are only copied to the Windows system32 directory.