diff --git a/quickcheck/src/main/java/quickcheck/plugin/QuickCheckThread.java b/quickcheck/src/main/java/quickcheck/plugin/QuickCheckThread.java
index 7eaede3e6..b05aeed0c 100644
--- a/quickcheck/src/main/java/quickcheck/plugin/QuickCheckThread.java
+++ b/quickcheck/src/main/java/quickcheck/plugin/QuickCheckThread.java
@@ -196,7 +196,7 @@ private JSONObject getQCResponse(ProofObligation po, List<VDMMessage> messages)
 			StringBuilder sb = new StringBuilder();
 			sb.append("PO #");
 			sb.append(po.number);
-			sb.append(" counterexample: ");
+			sb.append(" Counterexample: ");
 			sb.append(po.counterexample.toStringLine());
 			messages.add(new VDMWarning(9000, sb.toString(), po.location));
 		}