diff --git a/README b/README
index 32c401a..e745608 100644
--- a/README
+++ b/README
@@ -77,6 +77,6 @@
 -----------
 
 DISK on Chip support is currently disabled since it is considered unstable. 
-Change CFLAGS in the Makefile to enable it.
+Change CFLAGS in the Makefile to enable it: Remove -DDISABLE_DOC from CFLAGS.
 
 
diff --git a/flash_enable.c b/flash_enable.c
index ccd670a..e110f2a 100644
--- a/flash_enable.c
+++ b/flash_enable.c
@@ -506,11 +506,15 @@
 			}
 	}
 
-	/* now do the deed. */
-	if (enable) {
-		printf("Enabling flash write on %s...", enable->name);
-		if (enable->doit(dev, enable->name) == 0)
-			printf("OK\n");
+	if (!enable) {
+		printf("Warning: Unknown system. Flash detection "
+			"will most likely fail.\n");
+		return 1;
 	}
+	
+	/* now do the deed. */
+	printf("Enabling flash write on %s...", enable->name);
+	if (enable->doit(dev, enable->name) == 0)
+		printf("OK\n");
 	return 0;
 }