Library including? (Source conversion)

I decided that I wanted to give another shot at doing Flyff source work, but came to a halt when I opened Visual Studio .NET 2003. The IDE isn't working 100% properly for me (IntelliSense) and it's just generally outdated. I figured I'd port it to Visual Studio 2012 to be able to edit it with a nicer theme, but that stopped me as well when I ran into VC++ Including errors which around outside of my knowledge.

I started converting it one by one, beginning with the 'AccountServer'.
Since FlyFF's source dates back past my grandmother's last reincarnation, it still comes bundled with an over-aged 'DX_SDK'. Having this as an additional include causes these errors:

Code:

1>------ Rebuild All started: Project: AccountServer, Configuration: Debug Win32 ------ 1> StdAfx.cpp 1>c:\program files (x86)\windows kits\8.0\include\um\winnt.h(301): error C2146: syntax error : missing ';' before identifier 'PVOID64' 1>c:\program files (x86)\windows kits\8.0\include\um\winnt.h(301): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int 1>c:\program files (x86)\windows kits\8.0\include\um\winnt.h(11698): error C2146: syntax error : missing ';' before identifier 'Buffer' 1>c:\program files (x86)\windows kits\8.0\include\um\winnt.h(11698): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int ========== Rebuild All: 0 succeeded, 1 failed, 0 skipped ==========

My main question is, how should I go about including things? Is there anything that I should completely remove (deprecated)?

After doing some research I found out that a lot changed with DirectX. It is now integrated with the Windows SDK, which is causing these errors to pop up.
I removed the 'DX_SDK' include path and those particular errors were fixed, but of course, the Flyff source then missed old functionality that was replaced in the later versions of DirectX SDK (dplay.h).

Since this Flyff source is completely based around the old DirectX SDK I figured I should stick to that. Or is it worthwhile to convert the whole source to run off a later DirectX version?
Again, what should I do with the includes to make sure there's no incorrect hierarchy of important libraries?

P.S.: I'm using a Windows 7 Home Premium (64-Bit) machine. I've got the Windows 8.0 Kit that comes bundled with Visual Studio 2012.