1 files changed, 3 insertions, 2 deletions

diff --git a/src/Crypto/Tox.hs b/src/Crypto/Tox.hs
index 61a392e2..9b097c7e 100644
--- a/src/Crypto/Tox.hs
+++ b/src/Crypto/Tox.hs
@@ -470,8 +470,9 @@ instance Read Nonce32 where
                 '=':xs -> Right xs -- optional terminating '='
                 _      -> Right ss
         bs <- Base64.decode (C8.pack $ ds ++ ['='])
-        guard $ B.length bs == 32
-        return [ (Nonce32 bs, ss') ]
+        if B.length bs == 32
+            then Right [ (Nonce32 bs, ss') ]
+            else Left "Insuffiicent base64 digits while parsing Nonce32."
 
 instance Serialize Nonce32 where
     get = Nonce32 <$> getBytes 32