Well I had to implement a payment gateway at my server. My server was built on x64 architecture and had Windows Server 2008 installed. Well according to the document I had to put my COM dll inside c:\windows\system32 folder and then from Run command I had to register this dll like “regsvr32 c:\windows\system32\MyCOM.dll”.
Well I done above mentioned procedure successfully now I want to use this dll in my C# project so I create a project and go for add reference but even after successful registration my COM dll was not showing inside COM tab. I tried all possible way to add reference of this dll without any luck. I tried un-register, register as well as browsing this dll to add reference but nothing could help out me. So after doing some goggling and research I came to know that in x64 architecture there is a folder inside “c:\windows\” i.e. SysWOW64. This folder is specially designed for old 32 bit programs. Well if you are registering the old 32 bit COM dll or other 32 program then you should put the dll inside SysWOW64 folder and then register them from that location it will then use RegSvr32.exe of SysWOW64 folder for normal 64 bit dlls and other 64 bit programs u should put dlls inside System32 folder and run RegSvr32.exe from System32 folder.