diff --git a/windows/vs2015/libyara/libyara.vcxproj b/windows/vs2015/libyara/libyara.vcxproj
index c75c131c..88ddb0dd 100644
--- a/windows/vs2015/libyara/libyara.vcxproj
+++ b/windows/vs2015/libyara/libyara.vcxproj
@@ -222,6 +222,7 @@
     <ClCompile Include="..\..\..\libyara\ahocorasick.c" />
     <ClCompile Include="..\..\..\libyara\arena.c" />
     <ClCompile Include="..\..\..\libyara\atoms.c" />
+    <ClCompile Include="..\..\..\libyara\base64.c" />
     <ClCompile Include="..\..\..\libyara\bitmask.c" />
     <ClCompile Include="..\..\..\libyara\compiler.c" />
     <ClCompile Include="..\..\..\libyara\exec.c" />
diff --git a/windows/vs2017/libyara/libyara.vcxproj b/windows/vs2017/libyara/libyara.vcxproj
index 02d7430d..473ab02a 100644
--- a/windows/vs2017/libyara/libyara.vcxproj
+++ b/windows/vs2017/libyara/libyara.vcxproj
@@ -223,6 +223,7 @@
     <ClCompile Include="..\..\..\libyara\ahocorasick.c" />
     <ClCompile Include="..\..\..\libyara\arena.c" />
     <ClCompile Include="..\..\..\libyara\atoms.c" />
+    <ClCompile Include="..\..\..\libyara\base64.c" />
     <ClCompile Include="..\..\..\libyara\bitmask.c" />
     <ClCompile Include="..\..\..\libyara\compiler.c" />
     <ClCompile Include="..\..\..\libyara\exec.c" />