diff --git a/Types.hs b/Types.hs
index de8187f..5d26bed 100644
--- a/Types.hs
+++ b/Types.hs
@@ -37,11 +37,11 @@ import Metadata
 
 specTypeOfName :: (CSM m, Die m) => A.Name -> m A.SpecType
 specTypeOfName n
-    = liftM A.ndType (lookupName n)
+    = liftM A.ndType (lookupNameOrError n $ dieP (A.nameMeta n) $ "Could not find find type in specTypeOfName for: " ++ (show $ A.nameName n))
 
 abbrevModeOfName :: (CSM m, Die m) => A.Name -> m A.AbbrevMode
 abbrevModeOfName n
-    = liftM A.ndAbbrevMode (lookupName n)
+    = liftM A.ndAbbrevMode (lookupNameOrError n $ dieP (A.nameMeta n) $ "Could not find find abbreviation mode in abbrevModeOfName for: " ++ (show $ A.nameName n))
 
 typeOfName :: (CSM m, Die m) => A.Name -> m A.Type
 typeOfName n
diff --git a/Unnest.hs b/Unnest.hs
index d23f188..c493f46 100644
--- a/Unnest.hs
+++ b/Unnest.hs
@@ -134,7 +134,7 @@ removeFreeNames = doGeneric `extM` doSpecification `extM` doProcess
              -- Generate and define new names to replace them with
              newNamesS <- sequence [makeNonce (A.nameName n) | n <- freeNames]
              let newNames = [on { A.nameName = nn } | (on, nn) <- zip freeNames newNamesS]
-             onds <- mapM lookupName freeNames
+             onds <- mapM (\n -> lookupNameOrError n $ dieP mp $ "Could not find recorded type for free name: " ++ (show $ A.nameName n)) freeNames
              sequence_ [defineName nn (ond { A.ndName = A.nameName nn,
                                              A.ndAbbrevMode = am })
                         | (ond, nn, am) <- zip3 onds newNames ams]