Add try..catch in forms main.js

www/form/main.js

@@ -268,6 +268,7 @@ define([
                         var messages = obj.messages;
                         if (!messages.length) { return void cb(); }
                         if (obj.lastKnownHash !== answer.hash) { return void cb(); }
+                        try {
                             var res = Utils.Crypto.Mailbox.openOwnSecretLetter(messages[0].msg, {
                                 validateKey: data.validateKey,
                                 ephemeral_private: Nacl.util.decodeBase64(answer.curvePrivate),
@@ -278,6 +279,9 @@ define([
                             parsed._isAnon = answer.anonymous;
                             parsed._time = messages[0].time;
                             cb(parsed);
+                        } catch (e) {
+                            cb({error: e});
+                        }
                     });
 
                 });