To compile rbot/rxbot/urxbot/forbot/phatbot/agobot or somehting else.

you must:

You need Visual Studio 6.0 (Get it from wherever...) with (Download these) ...
  
Service Pack 5 (*)
Newest Platform SDK (Core SDK/Build Environment) (**) 
Newest Processor Pack (***)

(*)	http://msdn.microsoft.com/vstudio/downloads/updates/sp/vs6/sp5/ 
(**)	http://www.microsoft.com/msdownload/platformsdk/sdkupdate/
(***)	http://msdn.microsoft.com/vstudio/downloads/tools/ppack/download.aspx

Now...

A.Install SP5 

B.Install the Process Packer for VS C++

C.Install latest SDK/Core

D.Add these paths to VS:- 

"Tools|Options | Directories" in Visual Studio (be sure to include them on top of the list):
To Show directories for|Executable files: <path to sdk>\MICROSOFT SDK\BIN
To Show directories for|Include files: <path to sdk>\MICROSOFT SDK\INCLUDE
To Show directories for|Library files: <path to sdk>\MICROSOFT SDK\LIB 

Afternotes:
1. Make sure the added paths are on top of the list
2. You don't need the full SDK download, only Core SDK/Build Environment
3 Thats it..

Good Luck.