diff --git a/app/src/processing/app/Base.java b/app/src/processing/app/Base.java
index 7cc295433..e3c2ca2ca 100644
--- a/app/src/processing/app/Base.java
+++ b/app/src/processing/app/Base.java
@@ -1280,9 +1280,9 @@ public class Base {
       handleOpenUntitled(path);
 
     } catch (IOException e) {
-      Messages.showWarning("That's new to me",
-                           "A strange and unexplainable error occurred\n" +
-                           "while trying to create a new sketch.", e);
+      Messages.showTrace("That's new to me",
+                         "A strange and unexplainable error occurred\n" +
+                         "while trying to create a new sketch.", e, false);
     }
   }
 
diff --git a/app/src/processing/app/Util.java b/app/src/processing/app/Util.java
index 373415c4d..c27cf9e96 100644
--- a/app/src/processing/app/Util.java
+++ b/app/src/processing/app/Util.java
@@ -264,7 +264,7 @@ public class Util {
       final String urDum = "source and target directories are identical";
       throw new IllegalArgumentException(urDum);
     }
-    if (!targetDir.mkdirs()) {
+    if (!targetDir.exists() && !targetDir.mkdirs()) {
       throw new IOException("Could not create " + targetDir);
     }
     String[] filenames = sourceDir.list();
diff --git a/todo.txt b/todo.txt
index b310ea02b..93fe6eeba 100755
--- a/todo.txt
+++ b/todo.txt
@@ -1,4 +1,6 @@
 1286 (4.0.1)
+X Changing into p5.js mode gives an error
+X   https://github.com/processing/processing4/issues/530
 
 
 known issues