How to Use COM DLL in .NET

Question

Hi All, How to use a COM DLL in .NET? (I did add COM DLL thru Add Reference,and now without registering it z not working) DO we need to register COM DLL if we included in .NET application Is there any way to use COM DLL without registering. How to Create a Primary Interop Assembly.(Is it Using TlbImp.exe) Kindly give a reply with Example. Thanks ALL, V