riaz_muhammad wrote: Can you guide me step by step to make Managed Dll and send me small example for Managed DLL. Refer to the Visual Studio Walkthroughs[^] to get started with C++.NET. riaz_muhammad wrote: Should i use VC6 or VC.net for Manage dll development. You can not use VC6 to create a managed DLL. riaz_muhammad wrote: Now i am trying to use this dll in vb.net but result is not accurate. The reason is vc6 produce unmanage dll that vb.net cannot use. Now i need to make Managed dll. You CAN use your unmanaged DLL from VB.NET. Refer to the following MSDN help lik, Consuming Unmanaged DLL Functions[^]. Roger Stewart "I Owe, I Owe, it's off to work I go..."