diff --git a/indra/llcommon/StackWalker.h b/indra/llcommon/StackWalker.h
index 4634765d0b14b2e6006ab0569eed882bf37ca695..e2a257f6344423636132fd5f9704120c6bd75db3 100644
--- a/indra/llcommon/StackWalker.h
+++ b/indra/llcommon/StackWalker.h
@@ -43,7 +43,7 @@
 // so we need not to check the version (because we only support _MSC_VER >= 1100)!
 #pragma once
 
-#include <windows.h>
+#include "llwin32headerslean.h"
 
 // special defines for VC5/6 (if no actual PSDK is installed):
 #if _MSC_VER < 1300
diff --git a/indra/llcommon/llapp.cpp b/indra/llcommon/llapp.cpp
index cf1ade454fea8f604207281e5922ee761e231faa..a2df383d4f69b12696de355c2d5a7e54cac45b79 100644
--- a/indra/llcommon/llapp.cpp
+++ b/indra/llcommon/llapp.cpp
@@ -57,7 +57,7 @@
 // Windows uses structured exceptions, so it's handled a bit differently.
 //
 #if LL_WINDOWS
-#include "windows.h"
+#include "llwin32headerslean.h"
 
 LONG WINAPI default_windows_exception_handler(struct _EXCEPTION_POINTERS *exception_infop);
 BOOL ConsoleCtrlHandler(DWORD fdwCtrlType);
diff --git a/indra/llcommon/llmemory.cpp b/indra/llcommon/llmemory.cpp
index f80bb5001afa95d9e38bbec91904db8595972de7..0dd433f1b7c302ff586949b1af874472df0076b9 100644
--- a/indra/llcommon/llmemory.cpp
+++ b/indra/llcommon/llmemory.cpp
@@ -30,6 +30,7 @@
 #include "llthread.h"
 
 #if defined(LL_WINDOWS)
+#include "llwin32headerslean.h"
 # include <psapi.h>
 #elif defined(LL_DARWIN)
 # include <sys/types.h>
diff --git a/indra/llcommon/llprocess.h b/indra/llcommon/llprocess.h
index 0a0b6f0a3f8817cd490123c32feac4b6601faac8..0c3b4b02ea8efe127130e985a38d0f7e718d1817 100644
--- a/indra/llcommon/llprocess.h
+++ b/indra/llcommon/llprocess.h
@@ -29,7 +29,7 @@
 
 #include "llinitparam.h"
 #include "llsdparam.h"
-#include "llwin32headerslean.h"
+#include "llwin32headerslean.h"	// for HANDLE
 #include "llexception.h"
 #include "apr_thread_proc.h"
 #include <boost/shared_ptr.hpp>
@@ -38,9 +38,7 @@
 #include <boost/noncopyable.hpp>
 #include <iosfwd>                   // std::ostream
 
-#if LL_WINDOWS
-#include "llwin32headerslean.h"	// for HANDLE
-#elif LL_LINUX
+#if LL_LINUX
 #if defined(Status)
 #undef Status
 #endif
diff --git a/indra/llcommon/llprocinfo.cpp b/indra/llcommon/llprocinfo.cpp
index c00f979b0b2c6eaea049780973874d8058fd1040..1d0dfe315eed7b75712d0d9a9a957995d4c2a95a 100644
--- a/indra/llcommon/llprocinfo.cpp
+++ b/indra/llcommon/llprocinfo.cpp
@@ -30,9 +30,8 @@
 
 #if LL_WINDOWS
 
-#define	PSAPI_VERSION	1
-#include "windows.h"
-#include "psapi.h"
+#include "llwin32headerslean.h"
+#include <psapi.h>
 
 #elif LL_DARWIN
 
diff --git a/indra/llcommon/llsdutil.cpp b/indra/llcommon/llsdutil.cpp
index f53e7981e2b57ecd3c97c9a9c40dd454b4515e85..0d893023d800dea5a0438822f80605ef133f221c 100644
--- a/indra/llcommon/llsdutil.cpp
+++ b/indra/llcommon/llsdutil.cpp
@@ -31,8 +31,7 @@
 #include "llsdutil.h"
 
 #if LL_WINDOWS
-#	define WIN32_LEAN_AND_MEAN
-#	include <winsock2.h>	// for htonl
+#include "llwin32headerslean.h"
 #elif LL_LINUX || LL_SOLARIS
 #	include <netinet/in.h>
 #elif LL_DARWIN
diff --git a/indra/llcommon/llwin32headers.h b/indra/llcommon/llwin32headers.h
index 176efd2c11b6853313c9fc125cc860a27eb95c5b..84571b1ddfb0c4764b05a3b7d6bf3e0a7fbe56c1 100644
--- a/indra/llcommon/llwin32headers.h
+++ b/indra/llcommon/llwin32headers.h
@@ -31,10 +31,14 @@
 #ifndef NOMINMAX
 #define NOMINMAX
 #endif
+#ifndef PSAPI_VERSION
+#define	PSAPI_VERSION	2
+#endif
 #undef WIN32_LEAN_AND_MEAN
-#include <winsock2.h>
-#include <windows.h>
+#include <WinSock2.h>
+#include <Windows.h>
 #include <Ws2ipdef.h>
+#include <Psapi.h>
 // reset to default, which is lean
 #define WIN32_LEAN_AND_MEAN
 #undef NOMINMAX
diff --git a/indra/llcommon/llwin32headerslean.h b/indra/llcommon/llwin32headerslean.h
index 083d28c38bd6b0aef83404e99c4daf78fba33d58..5defc6b14015256dfe2f8772db0e6c0944778143 100644
--- a/indra/llcommon/llwin32headerslean.h
+++ b/indra/llcommon/llwin32headerslean.h
@@ -31,10 +31,16 @@
 #ifndef NOMINMAX
 #define NOMINMAX
 #endif
+#ifndef WIN32_LEAN_AND_MEAN
 #define WIN32_LEAN_AND_MEAN
+#endif
+#ifndef PSAPI_VERSION
+#define	PSAPI_VERSION	2
+#endif
 #include <winsock2.h>
 #include <windows.h>
 #include <Ws2ipdef.h>
+#include <psapi.h>
 #undef NOMINMAX
 #endif
 
diff --git a/indra/llmath/llsdutil_math.cpp b/indra/llmath/llsdutil_math.cpp
index 591f7fde360896bfe5846e71f771afff4975863e..208374c687698fa379539377fe9dd06eb61ca996 100644
--- a/indra/llmath/llsdutil_math.cpp
+++ b/indra/llmath/llsdutil_math.cpp
@@ -38,8 +38,7 @@
 #include "v4color.h"
 
 #if LL_WINDOWS
-#	define WIN32_LEAN_AND_MEAN
-#	include <winsock2.h>	// for htonl
+#include "llwin32headerslean.h"
 #elif LL_LINUX || LL_SOLARIS
 #	include <netinet/in.h>
 #elif LL_DARWIN
diff --git a/indra/llmessage/llcoproceduremanager.cpp b/indra/llmessage/llcoproceduremanager.cpp
index c348d274b16a6094078d04a2622e940b6d70f6da..35f82b3a2758efc8b804c03c6933ba50e68fdca6 100644
--- a/indra/llmessage/llcoproceduremanager.cpp
+++ b/indra/llmessage/llcoproceduremanager.cpp
@@ -25,7 +25,7 @@
 * $/LicenseInfo$
 */
 
-#include "llwin32headers.h"
+#include "llwin32headerslean.h"
 
 #include "linden_common.h"
 
diff --git a/indra/llmessage/llfiltersd2xmlrpc.cpp b/indra/llmessage/llfiltersd2xmlrpc.cpp
index d3e195789bf84222a0dc63d5f2ea13233fa53765..47e82557c6cfa844b9edc5a94a3e282c176e2989 100644
--- a/indra/llmessage/llfiltersd2xmlrpc.cpp
+++ b/indra/llmessage/llfiltersd2xmlrpc.cpp
@@ -71,6 +71,9 @@
  */
 
 #include "linden_common.h"
+
+#include "llwin32headerslean.h"
+
 #include "llfiltersd2xmlrpc.h"
 
 #include <sstream>
diff --git a/indra/llmessage/llhost.cpp b/indra/llmessage/llhost.cpp
index 00b32a676ab064f2b907713094a5fc5da0a5b635..8d1747d47c36ebdb7e1fb0816a680e8b65d32909 100644
--- a/indra/llmessage/llhost.cpp
+++ b/indra/llmessage/llhost.cpp
@@ -31,8 +31,7 @@
 #include "llerror.h"
 
 #if LL_WINDOWS
-	#define WIN32_LEAN_AND_MEAN
-	#include <winsock2.h>
+	#include "llwin32headerslean.h"
 #else
 	#include <netdb.h>
 	#include <netinet/in.h>	// ntonl()
diff --git a/indra/llmessage/llpacketring.cpp b/indra/llmessage/llpacketring.cpp
index 687212ea1069fa79ef99d2756b324d53c29ba3b4..a23d6c9fb6b2d0989a17cf1549e11559ee1e7638 100644
--- a/indra/llmessage/llpacketring.cpp
+++ b/indra/llmessage/llpacketring.cpp
@@ -29,7 +29,7 @@
 #include "llpacketring.h"
 
 #if LL_WINDOWS
-	#include <winsock2.h>
+	#include "llwin32headerslean.h"
 #else
 	#include <sys/socket.h>
 	#include <netinet/in.h>
diff --git a/indra/llmessage/llpumpio.h b/indra/llmessage/llpumpio.h
index b9eabee710f2584da95f378e1c689e54122e3496..1d656e15fff0e4fae9eaca72749ea02917d2749e 100644
--- a/indra/llmessage/llpumpio.h
+++ b/indra/llmessage/llpumpio.h
@@ -34,6 +34,7 @@
 #include <sys/param.h>
 #endif
 
+#include "llwin32headerslean.h"
 #include "apr_pools.h"
 #include "llbuffer.h"
 #include "llframetimer.h"
diff --git a/indra/llmessage/message.h b/indra/llmessage/message.h
index 5a07085a24b39085f4610cec3c334ddd36adacd2..4d4f5ad7cc50f318a161a5b6b9df18b191e150c7 100644
--- a/indra/llmessage/message.h
+++ b/indra/llmessage/message.h
@@ -40,7 +40,7 @@
 #endif
 
 #if LL_WINDOWS
-#include "winsock2.h" // htons etc.
+#include "llwin32headerslean.h" // htons etc.
 #endif
 
 #include "llerror.h"
diff --git a/indra/newview/llappviewerwin32.cpp b/indra/newview/llappviewerwin32.cpp
index f2f1f38bfb69e7d46a2c11658413695fdb98c6b4..418d6cc18c925ff12ae31eba56e3b60da8d91448 100644
--- a/indra/newview/llappviewerwin32.cpp
+++ b/indra/newview/llappviewerwin32.cpp
@@ -29,7 +29,7 @@
 #ifdef INCLUDE_VLD
 #include "vld.h"
 #endif
-#include "llwin32headers.h"
+#include "llwin32headerslean.h"
 
 #include "llwindowwin32.h" // *FIX: for setting gIconResource.
 
diff --git a/indra/newview/llfilepicker.h b/indra/newview/llfilepicker.h
index 4647ca949855f265a6194b8773318d13a6820c16..cdf5af45276607cdcd544c5c8639d4dfdac4933a 100644
--- a/indra/newview/llfilepicker.h
+++ b/indra/newview/llfilepicker.h
@@ -49,7 +49,7 @@
 
 // Need commdlg.h for OPENFILENAMEA
 #ifdef LL_WINDOWS
-#include "llwin32headers.h"
+#include "llwin32headerslean.h"
 #include <commdlg.h>
 #endif
 
diff --git a/indra/newview/llmeshrepository.cpp b/indra/newview/llmeshrepository.cpp
index 08733f64d445db8608b78990810f09d7b82b73dd..a8e291f5b8d7a7ae87d7c45700e54c1cb25d2a62 100644
--- a/indra/newview/llmeshrepository.cpp
+++ b/indra/newview/llmeshrepository.cpp
@@ -26,10 +26,6 @@
 
 #include "llviewerprecompiledheaders.h"
 
-#include "llapr.h"
-#include "apr_portable.h"
-#include "apr_pools.h"
-#include "apr_dso.h"
 #include "llhttpconstants.h"
 #include "llmeshrepository.h"
 
diff --git a/indra/newview/llviewerprecompiledheaders.h b/indra/newview/llviewerprecompiledheaders.h
index 6801d5e54ab89ad7e20b2690a2f69dddfa754709..6696891835e7cfab8d23e9347096fa6d0d6714a9 100644
--- a/indra/newview/llviewerprecompiledheaders.h
+++ b/indra/newview/llviewerprecompiledheaders.h
@@ -29,7 +29,7 @@
 #ifndef LL_LLVIEWERPRECOMPILEDHEADERS_H
 #define LL_LLVIEWERPRECOMPILEDHEADERS_H
 
-#include "llwin32headers.h"
+#include "llwin32headerslean.h"
 
 // This file MUST be the first one included by each .cpp file
 // in viewer.
diff --git a/indra/viewer_components/login/lllogin.cpp b/indra/viewer_components/login/lllogin.cpp
index 4909526d4b6758627d8f007c5c5231b9c7cad989..438e3b18dcb7699b550cc39c6ffc3c3d6c073500 100644
--- a/indra/viewer_components/login/lllogin.cpp
+++ b/indra/viewer_components/login/lllogin.cpp
@@ -23,8 +23,10 @@
  * $/LicenseInfo$
  */
 
-#include "llwin32headers.h"
 #include "linden_common.h"
+
+#include "llwin32headerslean.h"
+
 #include "llsd.h"
 #include "llsdutil.h"