diff --git a/src/TDB2.cpp b/src/TDB2.cpp
index ee6c38de7..353f3ac4b 100644
--- a/src/TDB2.cpp
+++ b/src/TDB2.cpp
@@ -839,7 +839,9 @@ void TDB2::revert ()
     //   - erase from completed
     //   - if in backlog, erase, else cannot undo
 
-    Task old = Task (prior);
+    Task old = Task ();
+    if (prior != "")
+      old = Task (prior);
     Context::getContext ().hooks.onModify (Task (current), old);
 
     // Modify other data files accordingly.