diff --git a/cmd/webp-manual-test/main.go b/cmd/webp-manual-test/main.go
index c041e21..296c763 100644
--- a/cmd/webp-manual-test/main.go
+++ b/cmd/webp-manual-test/main.go
@@ -38,13 +38,9 @@ var (
 
 func main() {
 	flag.Parse()
-	if *dwebp == "" {
+	if err := checkDwebp(); err != nil {
 		flag.Usage()
-		log.Fatal("dwebp flag was not specified")
-	}
-	if _, err := os.Stat(*dwebp); err != nil {
-		flag.Usage()
-		log.Fatalf("could not find dwebp program at %q", *dwebp)
+		log.Fatal(err)
 	}
 	if *testdata == "" {
 		flag.Usage()
@@ -81,6 +77,25 @@ func main() {
 	}
 }
 
+func checkDwebp() error {
+	if *dwebp == "" {
+		return fmt.Errorf("dwebp flag was not specified")
+	}
+	if _, err := os.Stat(*dwebp); err != nil {
+		return fmt.Errorf("could not find dwebp program at %q", *dwebp)
+	}
+	b, err := exec.Command(*dwebp, "-version").Output()
+	if err != nil {
+		return fmt.Errorf("could not determine the dwebp program version for %q: %v", *dwebp, err)
+	}
+	switch s := string(bytes.TrimSpace(b)); s {
+	case "0.4.0", "0.4.1", "0.4.2":
+		return fmt.Errorf("the dwebp program version %q for %q has a known bug "+
+			"(https://bugs.chromium.org/p/webp/issues/detail?id=239). Please use a newer version.", s, *dwebp)
+	}
+	return nil
+}
+
 // test tests a single WEBP image.
 func test(name string) error {
 	filename := filepath.Join(*testdata, name)