diff --git a/visual/VS2010/fullbench-dll/fullbench-dll.vcxproj b/visual/VS2010/fullbench-dll/fullbench-dll.vcxproj
index cb9ece6..16a4f0d 100644
--- a/visual/VS2010/fullbench-dll/fullbench-dll.vcxproj
+++ b/visual/VS2010/fullbench-dll/fullbench-dll.vcxproj
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<Project DefaultTargets="Build" ToolsVersion="14.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+<Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <ItemGroup Label="ProjectConfigurations">
     <ProjectConfiguration Include="Debug|Win32">
       <Configuration>Debug</Configuration>
diff --git a/visual/VS2010/liblz4-dll/liblz4-dll.vcxproj b/visual/VS2010/liblz4-dll/liblz4-dll.vcxproj
index 95dcbdd..389f13c 100644
--- a/visual/VS2010/liblz4-dll/liblz4-dll.vcxproj
+++ b/visual/VS2010/liblz4-dll/liblz4-dll.vcxproj
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<Project DefaultTargets="Build" ToolsVersion="14.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+<Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <ItemGroup Label="ProjectConfigurations">
     <ProjectConfiguration Include="Debug|Win32">
       <Configuration>Debug</Configuration>