diff --git a/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/MockSystemReader.java b/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/MockSystemReader.java
index 8de386e34..abbbf3296 100644
--- a/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/MockSystemReader.java
+++ b/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/MockSystemReader.java
@@ -80,6 +80,11 @@ public void load() throws IOException, ConfigInvalidException {
 			// Do nothing
 		}
 
+		@Override
+		public void save() throws IOException {
+			// Do nothing
+		}
+
 		@Override
 		public boolean isOutdated() {
 			return false;