diff --git a/RombaSharp/Partials/RombaSharp_Helpers.cs b/RombaSharp/Partials/RombaSharp_Helpers.cs
index 4d3b66cb..1f98a167 100644
--- a/RombaSharp/Partials/RombaSharp_Helpers.cs
+++ b/RombaSharp/Partials/RombaSharp_Helpers.cs
@@ -9,7 +9,7 @@ using SabreTools.Helper.Data;
 using SabreTools.Helper.Dats;
 using SabreTools.Helper.Tools;
 
-#if mono
+#if MONO
 using System.IO;
 #else
 using Alphaleonis.Win32.Filesystem;
diff --git a/RombaSharp/Partials/RombaSharp_Inits.cs b/RombaSharp/Partials/RombaSharp_Inits.cs
index 1ccfc437..7704640f 100644
--- a/RombaSharp/Partials/RombaSharp_Inits.cs
+++ b/RombaSharp/Partials/RombaSharp_Inits.cs
@@ -8,7 +8,7 @@ using SabreTools.Helper.Data;
 using SabreTools.Helper.Dats;
 using SabreTools.Helper.Tools;
 
-#if mono
+#if MONO
 using System.IO;
 #else
 using Alphaleonis.Win32.Filesystem;
diff --git a/RombaSharp/RombaSharp.csproj b/RombaSharp/RombaSharp.csproj
index bf2e9059..d5727cfc 100644
--- a/RombaSharp/RombaSharp.csproj
+++ b/RombaSharp/RombaSharp.csproj
@@ -65,7 +65,7 @@
   <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Mono|x64'">
     <DebugSymbols>true</DebugSymbols>
     <OutputPath>..\..\Debug-mono-x64</OutputPath>
-    <DefineConstants>TRACE;DEBUG;mono</DefineConstants>
+    <DefineConstants>TRACE;DEBUG;MONO</DefineConstants>
     <DebugType>full</DebugType>
     <PlatformTarget>x64</PlatformTarget>
     <ErrorReport>prompt</ErrorReport>
diff --git a/SabreTools.Helper/Dats/DatFile.cs b/SabreTools.Helper/Dats/DatFile.cs
index 5b1909dc..78b2bc91 100644
--- a/SabreTools.Helper/Dats/DatFile.cs
+++ b/SabreTools.Helper/Dats/DatFile.cs
@@ -11,7 +11,7 @@ using SabreTools.Helper.Data;
 using SabreTools.Helper.Skippers;
 using SabreTools.Helper.Tools;
 
-#if mono
+#if MONO
 using System.IO;
 #else
 using Alphaleonis.Win32.Filesystem;
diff --git a/SabreTools.Helper/Dats/DatItem.cs b/SabreTools.Helper/Dats/DatItem.cs
index 4014c049..5acd3bd8 100644
--- a/SabreTools.Helper/Dats/DatItem.cs
+++ b/SabreTools.Helper/Dats/DatItem.cs
@@ -4,7 +4,7 @@ using System.Collections.Generic;
 using SabreTools.Helper.Data;
 using SabreTools.Helper.Tools;
 
-#if mono
+#if MONO
 using System.IO;
 #else
 using Alphaleonis.Win32.Filesystem;
diff --git a/SabreTools.Helper/External/SupportedFiles/ZipFile.cs b/SabreTools.Helper/External/SupportedFiles/ZipFile.cs
index afa5faff..ae6eaa27 100644
--- a/SabreTools.Helper/External/SupportedFiles/ZipFile.cs
+++ b/SabreTools.Helper/External/SupportedFiles/ZipFile.cs
@@ -4,7 +4,7 @@ using System.Text;
 
 using SabreTools.Helper.Data;
 
-#if mono
+#if MONO
 using System.IO;
 #else
 using Alphaleonis.Win32.Filesystem;
diff --git a/SabreTools.Helper/External/Zlib/GZipStream.cs b/SabreTools.Helper/External/Zlib/GZipStream.cs
index 0c304632..d5ec6f4e 100644
--- a/SabreTools.Helper/External/Zlib/GZipStream.cs
+++ b/SabreTools.Helper/External/Zlib/GZipStream.cs
@@ -28,7 +28,7 @@
 
 using System;
 
-#if mono
+#if MONO
 using System.IO;
 #else
 using Alphaleonis.Win32.Filesystem;
diff --git a/SabreTools.Helper/SabreTools.Helper.csproj b/SabreTools.Helper/SabreTools.Helper.csproj
index 91836441..494be97d 100644
--- a/SabreTools.Helper/SabreTools.Helper.csproj
+++ b/SabreTools.Helper/SabreTools.Helper.csproj
@@ -62,7 +62,7 @@
   <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Mono|x64'">
     <DebugSymbols>true</DebugSymbols>
     <OutputPath>..\..\Debug-mono-x64</OutputPath>
-    <DefineConstants>TRACE;DEBUG;mono</DefineConstants>
+    <DefineConstants>TRACE;DEBUG;MONO</DefineConstants>
     <DebugType>full</DebugType>
     <PlatformTarget>x64</PlatformTarget>
     <ErrorReport>prompt</ErrorReport>
diff --git a/SabreTools.Helper/Skippers/Skipper.cs b/SabreTools.Helper/Skippers/Skipper.cs
index c6cf1093..b0544f84 100644
--- a/SabreTools.Helper/Skippers/Skipper.cs
+++ b/SabreTools.Helper/Skippers/Skipper.cs
@@ -6,7 +6,7 @@ using System.Xml;
 using SabreTools.Helper.Data;
 using SabreTools.Helper.Tools;
 
-#if mono
+#if MONO
 using System.IO;
 #else
 using Alphaleonis.Win32.Filesystem;
diff --git a/SabreTools.Helper/Skippers/SkipperRule.cs b/SabreTools.Helper/Skippers/SkipperRule.cs
index f596dbc5..c78a537c 100644
--- a/SabreTools.Helper/Skippers/SkipperRule.cs
+++ b/SabreTools.Helper/Skippers/SkipperRule.cs
@@ -3,7 +3,7 @@ using System.Collections.Generic;
 
 using SabreTools.Helper.Data;
 
-#if mono
+#if MONO
 using System.IO;
 #else
 using Alphaleonis.Win32.Filesystem;
diff --git a/SabreTools.Helper/Tools/ArchiveTools.cs b/SabreTools.Helper/Tools/ArchiveTools.cs
index c88ae7a2..b9669661 100644
--- a/SabreTools.Helper/Tools/ArchiveTools.cs
+++ b/SabreTools.Helper/Tools/ArchiveTools.cs
@@ -6,7 +6,7 @@ using System.Text.RegularExpressions;
 using SabreTools.Helper.Data;
 using SabreTools.Helper.Dats;
 
-#if mono
+#if MONO
 using System.IO;
 #else
 using Alphaleonis.Win32.Filesystem;
diff --git a/SabreTools.Helper/Tools/DatabaseTools.cs b/SabreTools.Helper/Tools/DatabaseTools.cs
index 10397764..1adb6210 100644
--- a/SabreTools.Helper/Tools/DatabaseTools.cs
+++ b/SabreTools.Helper/Tools/DatabaseTools.cs
@@ -3,7 +3,7 @@ using System;
 
 using SabreTools.Helper.Data;
 
-#if mono
+#if MONO
 using System.IO;
 #else
 using Alphaleonis.Win32.Filesystem;
diff --git a/SabreTools.Helper/Tools/FileTools.cs b/SabreTools.Helper/Tools/FileTools.cs
index 20c9e12d..d04edcd7 100644
--- a/SabreTools.Helper/Tools/FileTools.cs
+++ b/SabreTools.Helper/Tools/FileTools.cs
@@ -10,7 +10,7 @@ using SabreTools.Helper.Data;
 using SabreTools.Helper.Dats;
 using SabreTools.Helper.Skippers;
 
-#if mono
+#if MONO
 using System.IO;
 #else
 using Alphaleonis.Win32.Filesystem;
diff --git a/SabreTools.Helper/Tools/Style.cs b/SabreTools.Helper/Tools/Style.cs
index 21c41694..a158e236 100644
--- a/SabreTools.Helper/Tools/Style.cs
+++ b/SabreTools.Helper/Tools/Style.cs
@@ -9,7 +9,7 @@ using System.Web;
 using SabreTools.Helper.Data;
 using SabreTools.Helper.Dats;
 
-#if mono
+#if MONO
 using System.IO;
 #else
 using Alphaleonis.Win32.Filesystem;
diff --git a/SabreTools/Partials/SabreTools_Inits.cs b/SabreTools/Partials/SabreTools_Inits.cs
index afc259cb..3de8adf6 100644
--- a/SabreTools/Partials/SabreTools_Inits.cs
+++ b/SabreTools/Partials/SabreTools_Inits.cs
@@ -6,7 +6,7 @@ using SabreTools.Helper.Data;
 using SabreTools.Helper.Dats;
 using SabreTools.Helper.Tools;
 
-#if mono
+#if MONO
 using System.IO;
 #else
 using Alphaleonis.Win32.Filesystem;
diff --git a/SabreTools/SabreTools.cs b/SabreTools/SabreTools.cs
index a5e15406..f49643de 100644
--- a/SabreTools/SabreTools.cs
+++ b/SabreTools/SabreTools.cs
@@ -5,7 +5,7 @@ using SabreTools.Helper;
 using SabreTools.Helper.Data;
 using SabreTools.Helper.Tools;
 
-#if mono
+#if MONO
 using System.IO;
 #else
 using Alphaleonis.Win32.Filesystem;
diff --git a/SabreTools/SabreTools.csproj b/SabreTools/SabreTools.csproj
index e731dee4..282a9a1e 100644
--- a/SabreTools/SabreTools.csproj
+++ b/SabreTools/SabreTools.csproj
@@ -81,7 +81,7 @@
   <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Mono|x64'">
     <DebugSymbols>true</DebugSymbols>
     <OutputPath>..\..\Debug-mono-x64</OutputPath>
-    <DefineConstants>TRACE;DEBUG;mono</DefineConstants>
+    <DefineConstants>TRACE;DEBUG;MONO</DefineConstants>
     <DebugType>full</DebugType>
     <PlatformTarget>x64</PlatformTarget>
     <ErrorReport>prompt</ErrorReport>