diff --git a/IPhreeqc.MMS.vcxproj b/IPhreeqc.MMS.vcxproj
index a295f1cb..3ed317aa 100644
--- a/IPhreeqc.MMS.vcxproj
+++ b/IPhreeqc.MMS.vcxproj
@@ -230,6 +230,7 @@
       <WarningLevel>Level3</WarningLevel>
       <SuppressStartupBanner>true</SuppressStartupBanner>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <MultiProcessorCompilation>true</MultiProcessorCompilation>
     </ClCompile>
     <ResourceCompile>
       <PreprocessorDefinitions>_DEBUG;%(PreprocessorDefinitions)</PreprocessorDefinitions>
@@ -461,7 +462,16 @@
     <ClCompile Include="src\phreeqcpp\cvdense.cpp" />
     <ClCompile Include="src\phreeqcpp\cvode.cpp" />
     <ClCompile Include="src\phreeqcpp\dense.cpp" />
-    <ClCompile Include="src\phreeqcpp\dw.cpp" />
+    <ClCompile Include="src\phreeqcpp\dw.cpp">
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='ReleaseDll|Win32'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='DebugDll|Win32'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|x64'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='ReleaseDll|x64'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='DebugDll|x64'">true</ExcludedFromBuild>
+    </ClCompile>
     <ClCompile Include="src\phreeqcpp\gases.cpp" />
     <ClCompile Include="src\phreeqcpp\input.cpp" />
     <ClCompile Include="src\phreeqcpp\integrate.cpp" />