diff --git a/Annex/Environment.hs b/Annex/Environment.hs
index a066e9ab08..4f0fda986a 100644
--- a/Annex/Environment.hs
+++ b/Annex/Environment.hs
@@ -33,7 +33,7 @@ checkEnvironment = do
 
 checkEnvironmentIO :: IO ()
 checkEnvironmentIO = whenM (isNothing <$> myUserGecos) $ do
-	username <- myUserName
+	username <- either (const "unknown") id <$> myUserName
 	ensureEnv "GIT_AUTHOR_NAME" username
 	ensureEnv "GIT_COMMITTER_NAME" username
   where
@@ -52,7 +52,7 @@ ensureCommit :: Annex a -> Annex a
 ensureCommit a = either retry return =<< tryNonAsync a 
   where
 	retry _ = do
-		name <- liftIO myUserName
+		name <- liftIO $ either (const "unknown") id <$> myUserName
 		setConfig (ConfigKey "user.name") name
 		setConfig (ConfigKey "user.email") name
 		a
diff --git a/Annex/Init.hs b/Annex/Init.hs
index e12a8bc80f..08dd91a71f 100644
--- a/Annex/Init.hs
+++ b/Annex/Init.hs
@@ -52,13 +52,11 @@ genDescription (Just d) = return d
 genDescription Nothing = do
 	reldir <- liftIO . relHome =<< liftIO . absPath =<< fromRepo Git.repoPath
 	hostname <- fromMaybe "" <$> liftIO getHostname
-#ifndef mingw32_HOST_OS
 	let at = if null hostname then "" else "@"
-	username <- liftIO myUserName
-	return $ concat [username, at, hostname, ":", reldir]
-#else
-	return $ concat [hostname, ":", reldir]
-#endif
+	v <- liftIO myUserName
+	return $ concat $ case v of
+		Right username -> [username, at, hostname, ":", reldir]
+		Left _ -> [hostname, ":", reldir]
 
 initialize :: Maybe String -> Maybe Version -> Annex ()
 initialize mdescription mversion = do
diff --git a/Assistant/Gpg.hs b/Assistant/Gpg.hs
index 401b9aa75b..f9137dfb09 100644
--- a/Assistant/Gpg.hs
+++ b/Assistant/Gpg.hs
@@ -17,7 +17,7 @@ import qualified Data.Map as M
 newUserId :: GpgCmd -> IO UserId
 newUserId cmd = do
 	oldkeys <- secretKeys cmd
-	username <- myUserName
+	username <- either (const "unknown") id <$> myUserName
 	let basekeyname = username ++ "'s git-annex encryption key"
 	return $ Prelude.head $ filter (\n -> M.null $ M.filter (== n) oldkeys)
 		( basekeyname
diff --git a/Assistant/WebApp/Configurators/Pairing.hs b/Assistant/WebApp/Configurators/Pairing.hs
index 039676ac15..9b6de6c135 100644
--- a/Assistant/WebApp/Configurators/Pairing.hs
+++ b/Assistant/WebApp/Configurators/Pairing.hs
@@ -226,7 +226,7 @@ startLocalPairing stage oncancel alert muuid displaysecret secret = do
 		let pubkey = either error id $ validateSshPubKey $ sshPubKey keypair
 		pairdata <- liftIO $ PairData
 			<$> getHostname
-			<*> myUserName
+			<*> (either error id <$> myUserName)
 			<*> pure reldir
 			<*> pure pubkey
 			<*> (maybe genUUID return muuid)
@@ -291,8 +291,8 @@ promptSecret msg cont = pairPage $ do
 		let (username, hostname) = maybe ("", "")
 			(\(_, v, a) -> (T.pack $ remoteUserName v, T.pack $ fromMaybe (showAddr a) (remoteHostName v)))
 			(verifiableVal . fromPairMsg <$> msg)
-		u <- T.pack <$> liftIO myUserName
-		let sameusername = username == u
+		u <- liftIO myUserName
+		let sameusername = Right username == (T.pack <$> u)
 		$(widgetFile "configurators/pairing/local/prompt")
 
 {- This counts unicode characters as more than one character,
diff --git a/Assistant/WebApp/Configurators/Ssh.hs b/Assistant/WebApp/Configurators/Ssh.hs
index ce3d91a60e..5ad28402e4 100644
--- a/Assistant/WebApp/Configurators/Ssh.hs
+++ b/Assistant/WebApp/Configurators/Ssh.hs
@@ -156,10 +156,10 @@ getAddSshR :: Handler Html
 getAddSshR = postAddSshR
 postAddSshR :: Handler Html
 postAddSshR = sshConfigurator $ do
-	username <- liftIO $ T.pack <$> myUserName
+	username <- liftIO $ either (const Nothing) (Just . T.pack) <$> myUserName
 	((result, form), enctype) <- liftH $
 		runFormPostNoToken $ renderBootstrap3 bootstrapFormLayout $ sshInputAForm textField $
-			SshInput Nothing (Just username) Password Nothing Nothing 22
+			SshInput Nothing username Password Nothing Nothing 22
 	case result of
 		FormSuccess sshinput -> do
 			s <- liftAssistant $ testServer sshinput
diff --git a/Utility/UserInfo.hs b/Utility/UserInfo.hs
index c2edde24e5..ec0b0d0b2e 100644
--- a/Utility/UserInfo.hs
+++ b/Utility/UserInfo.hs
@@ -15,7 +15,7 @@ module Utility.UserInfo (
 ) where
 
 import Utility.Env
-import Utility.Exception
+import Utility.Data
 
 import System.PosixCompat
 import Control.Applicative
@@ -25,7 +25,7 @@ import Prelude
  -
  - getpwent will fail on LDAP or NIS, so use HOME if set. -}
 myHomeDir :: IO FilePath
-myHomeDir = myVal env homeDirectory
+myHomeDir = either error return =<< myVal env homeDirectory
   where
 #ifndef mingw32_HOST_OS
 	env = ["HOME"]
@@ -34,7 +34,7 @@ myHomeDir = myVal env homeDirectory
 #endif
 
 {- Current user's user name. -}
-myUserName :: IO String
+myUserName :: IO (Either String String)
 myUserName = myVal env userName
   where
 #ifndef mingw32_HOST_OS
@@ -48,15 +48,15 @@ myUserGecos :: IO (Maybe String)
 #if defined(__ANDROID__) || defined(mingw32_HOST_OS)
 myUserGecos = return Nothing
 #else
-myUserGecos = catchMaybeIO $ myVal [] userGecos
+myUserGecos = eitherToMaybe <$> myVal [] userGecos
 #endif
 
-myVal :: [String] -> (UserEntry -> String) -> IO String
+myVal :: [String] -> (UserEntry -> String) -> IO (Either String String)
 myVal envvars extract = go envvars
   where
 #ifndef mingw32_HOST_OS
-	go [] = extract <$> (getUserEntryForID =<< getEffectiveUserID)
+	go [] = Right . extract <$> (getUserEntryForID =<< getEffectiveUserID)
 #else
-	go [] = extract <$> error ("environment not set: " ++ show envvars)
+	go [] = return $ Left ("environment not set: " ++ show envvars)
 #endif
-	go (v:vs) = maybe (go vs) return =<< getEnv v
+	go (v:vs) = maybe (go vs) (return . Right) =<< getEnv v