diff --git a/libcvautomation/libcvautomation-xtest.c b/libcvautomation/libcvautomation-xtest.c
index f64bd86..e2fd03e 100644
--- a/libcvautomation/libcvautomation-xtest.c
+++ b/libcvautomation/libcvautomation-xtest.c
@@ -504,8 +504,10 @@ void xte_clickKey ( Display *displayLocation, char *key )
 	KeySym ks;
 
 	ks = XStringToKeysym( key );
-	if ( ks == NoSymbol )
-		return;
+    if ( ks == NoSymbol ) {
+        fprintf( stderr, "Key '%s' is an unknown key\n", key );
+        return;
+    }
 
 	kc = XKeysymToKeycode( displayLocation, ks );