diff --git a/build/windows/config-cmd.xml b/build/windows/config-cmd.xml
old mode 100644
new mode 100755
index 010ab775e..117abf3de
--- a/build/windows/config-cmd.xml
+++ b/build/windows/config-cmd.xml
@@ -30,7 +30,7 @@
   <jre>
     <path>java</path>
     <!-- Deal with jokers who install JOGL, ANTLR, etc system-wide -->
-    <opt>-Djava.ext.dirs=lib/ext</opt>
+    <opt>-Djava.ext.dirs=%EXEDIR%/java/lib/ext</opt>
     <!-- Prevent a user-installed JNA from conflicting with our version.
          https://github.com/processing/processing/issues/2239 -->
     <opt>-Djna.nosys=true</opt>
diff --git a/build/windows/config.xml b/build/windows/config.xml
old mode 100644
new mode 100755
index a3b83a0d0..c95c33a82
--- a/build/windows/config.xml
+++ b/build/windows/config.xml
@@ -27,7 +27,7 @@
   <jre>
     <path>java</path>
     <!-- Deal with jokers who install JOGL, ANTLR, etc system-wide -->
-    <opt>-Djava.ext.dirs=lib/ext</opt>
+    <opt>-Djava.ext.dirs=%EXEDIR%/java/lib/ext</opt>
     <!-- https://github.com/processing/processing/issues/2239 -->
     <opt>-Djna.nosys=true</opt>
     <!-- Because nosys is set to true, the DLL in the current working 
diff --git a/java/src/processing/mode/java/JavaBuild.java b/java/src/processing/mode/java/JavaBuild.java
old mode 100644
new mode 100755
index b10b010e3..42aa1a9f9
--- a/java/src/processing/mode/java/JavaBuild.java
+++ b/java/src/processing/mode/java/JavaBuild.java
@@ -1135,7 +1135,7 @@ public class JavaBuild {
     // https://github.com/processing/processing/issues/2239
     runOptions.add("-Djna.nosys=true");
     // https://github.com/processing/processing/issues/4608
-    runOptions.add("-Djava.ext.dirs=lib/ext");
+    runOptions.add("-Djava.ext.dirs=%EXEDIR%/java/lib/ext");
     // https://github.com/processing/processing/issues/2559
     if (exportPlatform == PConstants.WINDOWS) {
       runOptions.add("-Djava.library.path=\"%EXEDIR%\\lib\"");
diff --git a/todo.txt b/todo.txt
old mode 100644
new mode 100755
index e888920b4..e11dadbab
--- a/todo.txt
+++ b/todo.txt
@@ -10,8 +10,8 @@ X   https://github.com/processing/processing/issues/4128
 X   https://github.com/processing/processing/issues/4503
 _   test ext.dirs working on Linux (use js example)
 _   test ext.dirs on exported app on Linux
-_   test ext.dirs working on Windows (use js example)
-_   test ext.dirs on exported app on Windows
+X   test ext.dirs working on Windows (use js example)
+X   modify ext.dirs for exported apps on Windows
 X see if CLASSPATH can be set to screw up p5
 X   works fine on OS X, couldn't reproduce on Linux
 X rewrite Util.listFiles() because it wasn't working properly