diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,3 +1,9 @@
+## 0.2.0.0
+
+* Clearer error messages on crash
+* Exception on invalid credentials
+* Exception on too many failed logins
+
 ## 0.1.0.1
 
 * Executable: support for only downloading one list
diff --git a/myanimelist-export.cabal b/myanimelist-export.cabal
--- a/myanimelist-export.cabal
+++ b/myanimelist-export.cabal
@@ -1,5 +1,5 @@
 name:                myanimelist-export
-version:             0.1.0.1
+version:             0.2.0.0
 synopsis:            Export from MyAnimeList
 description:
     Export anime or manga lists from MyAnimeList in XML format.  Uses the web
@@ -29,6 +29,7 @@
                      , bytestring        >= 0.10 && < 0.11
                      , conduit           >= 1.2  && < 1.3
                      , containers        >= 0.5  && < 0.6
+                     , exceptions        >= 0.4  && < 0.9
                      , http-client       >= 0.5  && < 0.6
                      , network-uri       >= 2.6  && < 2.7
                      , tagstream-conduit >= 0.5  && < 0.6
diff --git a/src/MemoizedTraverse.hs b/src/MemoizedTraverse.hs
--- a/src/MemoizedTraverse.hs
+++ b/src/MemoizedTraverse.hs
@@ -28,7 +28,7 @@
                  -> t a
                  -> f (t b)
 memoizedTraverse f xs = vals <&> \vals' ->
-    lookupErr "memoizedTraverse" vals' <$> xs
+    lookupErr "myanimelist-export:memoizedTraverse: lookup error" vals' <$> xs
   where
     keys = foldl' (flip (flip M.insert ())) M.empty xs
     vals = M.traverseWithKey (\k () -> f k) keys
diff --git a/src/MyAnimeList/Export.hs b/src/MyAnimeList/Export.hs
--- a/src/MyAnimeList/Export.hs
+++ b/src/MyAnimeList/Export.hs
@@ -30,6 +30,7 @@
 module MyAnimeList.Export
     ( MediaType(..)
     , exportLists
+    , MyAnimeListException(..)
     ) where
 
 import           Data.Function
@@ -37,6 +38,8 @@
 import           Control.Monad
 import           Control.Monad.IO.Class
 
+import           Control.Monad.Catch (MonadThrow, Exception, throwM)
+
 import           Control.Concurrent.Async (Concurrently(Concurrently),
                                            runConcurrently)
 
@@ -51,7 +54,7 @@
 import qualified Data.Conduit.List as C
 
 import           Text.HTML.TagStream.ByteString (Token, tokenStream)
-import           Text.HTML.TagStream            (Token' (TagOpen))
+import           Text.HTML.TagStream            (Token' (TagOpen, Text))
 
 import           Network.URI         (URI, parseURIReference, uriPath,
                                       relativeTo)
@@ -64,6 +67,12 @@
 data MediaType = Anime | Manga
   deriving (Read, Show, Eq, Ord, Enum)
 
+-- | Possible exceptions that could be raised by `exportLists`
+data MyAnimeListException = InvalidCredentials -- ^ Wrong username/password
+                          | TooManyAttempts    -- ^ Too many failed logins
+  deriving (Read, Show, Eq, Ord)
+instance Exception MyAnimeListException
+
 newtype CSRF = CSRF { unCsrf :: ByteString }
 
 
@@ -79,7 +88,18 @@
 malExportPath :: String
 malExportPath = "/export/download.php"
 
+-- | Known MyAnimeList error messages with the corresponding exceptions
+malErrorMap :: [(ByteString, MyAnimeListException)]
+malErrorMap = [ ("Your username or password is incorrect.", InvalidCredentials)
+              , ("Too many failed login attempts, your IP address has been blocked for several hours.", TooManyAttempts)
+              ]
 
+lookupErrorMap :: ByteString -> Maybe MyAnimeListException
+lookupErrorMap t = case filter (\(m,_) -> BS.isInfixOf m t) malErrorMap of
+    []         -> Nothing
+    ((_, e):_) -> Just e
+
+
 -- | Export list(s) and return URL(s) to gzipped XML
 exportLists :: (Functor f, Foldable f)
             => Text        -- ^ Username
@@ -99,8 +119,11 @@
       -> CSRF
       -> Manager
       -> IO CookieJar
-login username password cj csrf manager = withResponse req manager $
-    pure . responseCookieJar
+login username password cj csrf manager = withResponse req manager $ \res -> do
+    runConduit $ sourceBodyReader (responseBody res)
+              .| tokenStream
+              .| awaitForever tagToLoginError
+    pure $ responseCookieJar res
   where
     req = urlEncodedBody [ ("user_name", encodeUtf8 username)
                          , ("password", encodeUtf8 password)
@@ -116,8 +139,9 @@
     runConduit $ sourceBodyReader (responseBody res)
               .| tokenStream
               .| C.mapMaybe tagToCsrf
-              .| (await >>= maybe (fail "getCsrf")
-                                  (pure . (,) (responseCookieJar res))
+              .| (await >>= maybe
+                           (fail $ moduleName ++ ".getCsrf: couldn't find csrf")
+                           (pure . (,) (responseCookieJar res))
                  )
 
 exportList :: CookieJar
@@ -131,8 +155,9 @@
               .| C.mapMaybe tagToUri
               .| C.filter ((malExportPath ==) . uriPath)
               .| C.map (`relativeTo` getUri malHomePage)
-              .| (await >>= maybe (fail "exportList")
-                                  pure
+              .| (await >>= maybe
+                         (fail $ moduleName ++ ".exportList: couldn't find uri")
+                         pure
                  )
   where
     req = urlEncodedBody [ ("type", mediaTypeValue mediaType)
@@ -158,6 +183,23 @@
     parseURIReference . B8.unpack =<< lookup "href" xs
 tagToUri _ = Nothing
 
+tagToLoginError :: MonadThrow m => Token -> ConduitM Token o m ()
+tagToLoginError (TagOpen "div" xs False)
+    | lookup "class" xs == Just "badresult" = do
+        nextTag <- await
+        case nextTag of
+            Just (Text t)
+                | Just e <- lookupErrorMap t -> throwM e
+            Just e -> failM $ moduleName ++ ".login: unknown error: " ++ show e
+            Nothing -> failM $ moduleName ++ ".login: unexpected end of stream"
+tagToLoginError _ = pure ()
+
 mediaTypeValue :: MediaType -> ByteString
 mediaTypeValue Anime = "1"
 mediaTypeValue Manga = "2"
+
+moduleName :: String
+moduleName = "MyAnimeList.Export"
+
+failM :: MonadThrow m => String -> m a
+failM = throwM . userError