diff --git a/build-windows/generate_code.cmd b/build-windows/generate_code.cmd
index d9f58beb..a36226ba 100644
--- a/build-windows/generate_code.cmd
+++ b/build-windows/generate_code.cmd
@@ -13,6 +13,11 @@ xcopy /y generated\*.h ..\src\
 
 cd %1\asn.1
 
+del *.h*
+del *.c*
+
 ..\..\Tools\asn1c\bin\asn1c -S ../../Tools/asn1c/share/asn1c -gen-PER -fincludes-quoted -fcompound-names -pdu=auto pEp.asn1 keysync.asn1 sync.asn1
 
+del *-sample.c
+
 popd
diff --git a/build-windows/pEpEngine.vcxproj b/build-windows/pEpEngine.vcxproj
index 05727518..4bf36821 100644
--- a/build-windows/pEpEngine.vcxproj
+++ b/build-windows/pEpEngine.vcxproj
@@ -68,7 +68,7 @@
       <AdditionalDependencies>$(TargetDir)\pEpEngineASN1.lib;Rpcrt4.lib;%(AdditionalDependencies)</AdditionalDependencies>
     </Link>
     <PreBuildEvent>
-      <Command>cmd /c "$(ProjectDir)build_windows\generate_code.cmd" "$(ProjectDir)"
+      <Command>"$(SysProjectDir)generate_code.cmd" "$(ProjectDir).."
 </Command>
     </PreBuildEvent>
   </ItemDefinitionGroup>
@@ -95,7 +95,7 @@
       <AdditionalDependencies>$(TargetDir)\pEpEngineASN1.lib;Rpcrt4.lib;%(AdditionalDependencies)</AdditionalDependencies>
     </Link>
     <PreBuildEvent>
-      <Command>cmd /c "$(ProjectDir)build_windows\generate_code.cmd" "$(ProjectDir)"
+      <Command>"$(SysProjectDir)generate_code.cmd" "$(ProjectDir).."
 </Command>
     </PreBuildEvent>
   </ItemDefinitionGroup>