diff --git a/src/park.c b/src/park.c
index bb7413f0fa..7fc5d11c55 100644
--- a/src/park.c
+++ b/src/park.c
@@ -18,6 +18,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *****************************************************************************/
 
+#include <windows.h>
 #include "addresses.h"
 #include "finance.h"
 #include "map.h"
diff --git a/src/rct2.c b/src/rct2.c
index e3ac83c096..d857b093ac 100644
--- a/src/rct2.c
+++ b/src/rct2.c
@@ -23,7 +23,7 @@
 #include <string.h>
 #include <setjmp.h>
 #include <windows.h>
-#include <ShlObj.h>
+#include <shlobj.h>
 #include <SDL.h>
 #include "addresses.h"
 #include "climate.h"
@@ -338,7 +338,7 @@ void get_system_info()
 	RCT2_GLOBAL(RCT2_ADDRESS_MEM_TOTAL_PAGEFILE, uint32) = memInfo.dwTotalPageFile;
 	RCT2_GLOBAL(RCT2_ADDRESS_MEM_TOTAL_VIRTUAL, uint32) = memInfo.dwTotalVirtual;
 
-	uint32 size = 80;
+	DWORD size = 80;
 	GetUserName((char*)RCT2_ADDRESS_OS_USER_NAME, &size);
 	size = 80;
 	GetComputerName((char*)RCT2_ADDRESS_OS_COMPUTER_NAME, &size);
diff --git a/src/rct2.h b/src/rct2.h
index d0a75a23ed..41c49d30d2 100644
--- a/src/rct2.h
+++ b/src/rct2.h
@@ -44,7 +44,7 @@ typedef unsigned long long uint64;
 #define sgn(x)				((x > 0) ? 1 : ((x < 0) ? -1 : 0))
 #define clamp(l, x, h)		(min(h, max(l, x)))
 
-#define countof(x)			_countof(x)
+#define countof(x)			((sizeof(x)/sizeof(0[x])) / ((size_t)(!(sizeof(x) % sizeof(0[x])))))
 
 void rct2_finish();
 
diff --git a/src/ride.c b/src/ride.c
index 42f32287ff..7490f60dd3 100644
--- a/src/ride.c
+++ b/src/ride.c
@@ -18,6 +18,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *****************************************************************************/
 
+#include <windows.h>
 #include "addresses.h"
 #include "ride.h"
 #include "sprite.h"
diff --git a/src/sawyercoding.c b/src/sawyercoding.c
index f62483f5c2..3b56e5806c 100644
--- a/src/sawyercoding.c
+++ b/src/sawyercoding.c
@@ -111,7 +111,7 @@ int sawyercoding_read_chunk(HANDLE hFile, uint8 *buffer)
 static int decode_chunk_rle(char *buffer, int length)
 {
 	int i, j, count;
-	uint8 *src, *dst, rleCodeByte;
+	char *src, *dst, rleCodeByte;
 
 	// Backup buffer
 	src = malloc(length);
@@ -145,7 +145,7 @@ static int decode_chunk_rle(char *buffer, int length)
 static int decode_chunk_repeat(char *buffer, int length)
 {
 	int i, j, count;
-	uint8 *src, *dst, *copyOffset;
+	char *src, *dst, *copyOffset;
 
 	// Backup buffer
 	src = malloc(length);
diff --git a/src/title.c b/src/title.c
index 5240805f3b..d351270bc9 100644
--- a/src/title.c
+++ b/src/title.c
@@ -18,6 +18,7 @@
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *****************************************************************************/
 
+#include <windows.h>
 #include <string.h>
 #include <time.h>
 #include "addresses.h"
diff --git a/src/widget.c b/src/widget.c
index 33be565a97..cae3647fc0 100644
--- a/src/widget.c
+++ b/src/widget.c
@@ -18,6 +18,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *****************************************************************************/
 
+#include <windows.h>
 #include <memory.h>
 #include <stdlib.h>
 #include "addresses.h"
diff --git a/src/window_about.c b/src/window_about.c
index d659b7c5f0..36159bdce0 100644
--- a/src/window_about.c
+++ b/src/window_about.c
@@ -18,6 +18,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *****************************************************************************/
 
+#include <windows.h>
 #include <string.h>
 #include "addresses.h"
 #include "string_ids.h"
diff --git a/src/window_cheats.c b/src/window_cheats.c
index 7974617fbb..0a18ff0ada 100644
--- a/src/window_cheats.c
+++ b/src/window_cheats.c
@@ -18,7 +18,9 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *****************************************************************************/
 
+#include <windows.h>
 #include <string.h>
+#include <limits.h>
 #include "addresses.h"
 #include "park.h"
 #include "peep.h"
diff --git a/src/window_dropdown.c b/src/window_dropdown.c
index 59bd42a92a..4b552e7d80 100644
--- a/src/window_dropdown.c
+++ b/src/window_dropdown.c
@@ -18,6 +18,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *****************************************************************************/
 
+#include <windows.h>
 #include <memory.h>
 #include "addresses.h"
 #include "scenario.h"
diff --git a/src/window_game_bottom_toolbar.c b/src/window_game_bottom_toolbar.c
index e8c3a1ab22..3966c3904f 100644
--- a/src/window_game_bottom_toolbar.c
+++ b/src/window_game_bottom_toolbar.c
@@ -18,6 +18,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *****************************************************************************/
 
+#include <windows.h>
 #include <string.h>
 #include "addresses.h"
 #include "climate.h"
diff --git a/src/window_tooltip.c b/src/window_tooltip.c
index 643671f568..fc8ebbb22f 100644
--- a/src/window_tooltip.c
+++ b/src/window_tooltip.c
@@ -18,6 +18,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *****************************************************************************/
 
+#include <windows.h>
 #include <memory.h>
 #include "addresses.h"
 #include "string_ids.h"