diff --git a/win32/Analysis/Analysis.vcproj b/win32/Analysis/Analysis.vcproj
index 4eb0bf3eb99..cfe6adbaa19 100644
--- a/win32/Analysis/Analysis.vcproj
+++ b/win32/Analysis/Analysis.vcproj
@@ -70,7 +70,7 @@
 				RuntimeTypeInfo="TRUE"
 				UsePrecompiledHeader="0"
 				WarningLevel="3"
-				Detect64BitPortabilityProblems="TRUE"
+				Detect64BitPortabilityProblems="FALSE"
 				DebugInformationFormat="3"
 				DisableSpecificWarnings="4146,4800"/>
 			<Tool
diff --git a/win32/CodeGen/CodeGen.vcproj b/win32/CodeGen/CodeGen.vcproj
index 738a2318e9e..3b5d80173e5 100644
--- a/win32/CodeGen/CodeGen.vcproj
+++ b/win32/CodeGen/CodeGen.vcproj
@@ -70,7 +70,7 @@
 				RuntimeTypeInfo="TRUE"
 				UsePrecompiledHeader="0"
 				WarningLevel="3"
-				Detect64BitPortabilityProblems="TRUE"
+				Detect64BitPortabilityProblems="FALSE"
 				DebugInformationFormat="3"
 				DisableSpecificWarnings="4146,4800"/>
 			<Tool
diff --git a/win32/ExecutionEngine/ExecutionEngine.vcproj b/win32/ExecutionEngine/ExecutionEngine.vcproj
index b5e959bb427..974046636f6 100644
--- a/win32/ExecutionEngine/ExecutionEngine.vcproj
+++ b/win32/ExecutionEngine/ExecutionEngine.vcproj
@@ -70,7 +70,7 @@
 				RuntimeTypeInfo="TRUE"
 				UsePrecompiledHeader="0"
 				WarningLevel="3"
-				Detect64BitPortabilityProblems="TRUE"
+				Detect64BitPortabilityProblems="FALSE"
 				DebugInformationFormat="3"
 				DisableSpecificWarnings="4146,4800"/>
 			<Tool
diff --git a/win32/Fibonacci/Fibonacci.vcproj b/win32/Fibonacci/Fibonacci.vcproj
index 2db0f237ce9..12637b3b44a 100644
--- a/win32/Fibonacci/Fibonacci.vcproj
+++ b/win32/Fibonacci/Fibonacci.vcproj
@@ -83,7 +83,7 @@
 				RuntimeTypeInfo="TRUE"
 				UsePrecompiledHeader="0"
 				WarningLevel="3"
-				Detect64BitPortabilityProblems="TRUE"
+				Detect64BitPortabilityProblems="FALSE"
 				DebugInformationFormat="3"
 				DisableSpecificWarnings="4146,4800"/>
 			<Tool
diff --git a/win32/Support/Support.vcproj b/win32/Support/Support.vcproj
index 1071aa0d0d2..5a17739db00 100644
--- a/win32/Support/Support.vcproj
+++ b/win32/Support/Support.vcproj
@@ -71,7 +71,7 @@
 				RuntimeTypeInfo="TRUE"
 				UsePrecompiledHeader="0"
 				WarningLevel="3"
-				Detect64BitPortabilityProblems="TRUE"
+				Detect64BitPortabilityProblems="FALSE"
 				DebugInformationFormat="3"
 				DisableSpecificWarnings="4146,4800"/>
 			<Tool
diff --git a/win32/System/System.vcproj b/win32/System/System.vcproj
index c63f020cd44..ae115d30e79 100644
--- a/win32/System/System.vcproj
+++ b/win32/System/System.vcproj
@@ -71,7 +71,7 @@
 				RuntimeTypeInfo="TRUE"
 				UsePrecompiledHeader="0"
 				WarningLevel="3"
-				Detect64BitPortabilityProblems="TRUE"
+				Detect64BitPortabilityProblems="FALSE"
 				DebugInformationFormat="3"
 				DisableSpecificWarnings="4146,4800"/>
 			<Tool
diff --git a/win32/TableGen/TableGen.vcproj b/win32/TableGen/TableGen.vcproj
index ad872d192ff..599e67cfae1 100644
--- a/win32/TableGen/TableGen.vcproj
+++ b/win32/TableGen/TableGen.vcproj
@@ -79,7 +79,7 @@
 				RuntimeTypeInfo="TRUE"
 				UsePrecompiledHeader="0"
 				WarningLevel="3"
-				Detect64BitPortabilityProblems="TRUE"
+				Detect64BitPortabilityProblems="FALSE"
 				DebugInformationFormat="3"
 				DisableSpecificWarnings="4146,4800"/>
 			<Tool
diff --git a/win32/Target/Target.vcproj b/win32/Target/Target.vcproj
index 42c1309ebd2..1378ace85a8 100644
--- a/win32/Target/Target.vcproj
+++ b/win32/Target/Target.vcproj
@@ -70,7 +70,7 @@
 				RuntimeTypeInfo="TRUE"
 				UsePrecompiledHeader="0"
 				WarningLevel="3"
-				Detect64BitPortabilityProblems="TRUE"
+				Detect64BitPortabilityProblems="FALSE"
 				DebugInformationFormat="3"
 				DisableSpecificWarnings="4146,4800"/>
 			<Tool
diff --git a/win32/Transforms/Transforms.vcproj b/win32/Transforms/Transforms.vcproj
index c4897d9e0b8..bfcb33f6002 100644
--- a/win32/Transforms/Transforms.vcproj
+++ b/win32/Transforms/Transforms.vcproj
@@ -70,7 +70,7 @@
 				RuntimeTypeInfo="TRUE"
 				UsePrecompiledHeader="0"
 				WarningLevel="3"
-				Detect64BitPortabilityProblems="TRUE"
+				Detect64BitPortabilityProblems="FALSE"
 				DebugInformationFormat="3"
 				DisableSpecificWarnings="4146,4800"/>
 			<Tool
diff --git a/win32/VMCore/VMCore.vcproj b/win32/VMCore/VMCore.vcproj
index 5f404465505..fce64fbaab2 100644
--- a/win32/VMCore/VMCore.vcproj
+++ b/win32/VMCore/VMCore.vcproj
@@ -70,7 +70,7 @@
 				RuntimeTypeInfo="TRUE"
 				UsePrecompiledHeader="0"
 				WarningLevel="3"
-				Detect64BitPortabilityProblems="TRUE"
+				Detect64BitPortabilityProblems="FALSE"
 				DebugInformationFormat="3"
 				DisableSpecificWarnings="4146,4800"/>
 			<Tool
diff --git a/win32/x86/x86.vcproj b/win32/x86/x86.vcproj
index ea979be094c..33100649e7a 100644
--- a/win32/x86/x86.vcproj
+++ b/win32/x86/x86.vcproj
@@ -79,7 +79,7 @@
 				RuntimeTypeInfo="TRUE"
 				UsePrecompiledHeader="0"
 				WarningLevel="3"
-				Detect64BitPortabilityProblems="TRUE"
+				Detect64BitPortabilityProblems="FALSE"
 				DebugInformationFormat="3"
 				DisableSpecificWarnings="4146,4800"/>
 			<Tool