Converting unmanaged C++ code from 32 bit to 64 bit

I have an unmanaged C++ 32 bit application that produces a dll. Now, I want to build it for 64 bit system. My development system is 32 bit. It uses oledb.lib activeds.lib adsiid.lib ws2_32.lib libraries to build the dll. What I have done so far is : Changed the configuration settings and set the Active solution platform to x64. It built the application successfully. But I could not register the dll on a 64 bit machine. While I tried to do so, I got the following error:

Unable to load DLL C:\Windows\System32\KBTicketExperience.dll

Process Name: dllhost.exe

Comsvcs.dll file version: ENU 2001.12.8530.16385 shp during com开发者_如何转开发ponent registration. Unable to validate DLL entry points.

Would you please tell me how to get rid of this problem? Thanks in advance.

I recommend creating a new project/workspace to build this DLL that is 64-bit through and through--no 32-bit anything. Assuming the DLL that this project works, you can look more closely at the differences between the projects and got from there.