diff --git a/Implab/ActionChainTaskBase.cs b/Implab/ActionChainTaskBase.cs
--- a/Implab/ActionChainTaskBase.cs
+++ b/Implab/ActionChainTaskBase.cs
@@ -50,7 +50,7 @@ namespace Implab {
                     p.On(SetResult, SetErrorInternal, SetCancelledInternal);
                     CancellationRequested(p.Cancel);
                 } catch (Exception err) {
-                    SetErrorInternal(error);
+                    SetErrorInternal(err);
                 }
             } else {
                 SetErrorInternal(error);