MongoError: E11000 duplicate key error index: b2urh52bh95t.users.$email_1 dup key: { : null } at Db.wrap (/home/www/git/cnode/node_modules/mongoose/node_modules/mongodb/lib/mongodb/db.js:1875:11) at null.<anonymous> (/home/www/git/cnode/node_modules/mongoose/node_modules/mongodb/lib/mongodb/collection.js:320:26) at g (events.js:180:16) at EventEmitter.emit (events.js:106:17) at Db._callHandler (/home/www/git/cnode/node_modules/mongoose/node_modules/mongodb/lib/mongodb/db.js:1413:25) at /home/www/git/cnode/node_modules/mongoose/node_modules/mongodb/lib/mongodb/connection/server.js:421:30 at MongoReply.parseBody (/home/www/git/cnode/node_modules/mongoose/node_modules/mongodb/lib/mongodb/responses/mongo_reply.js:127:5) at null.<anonymous> (/home/www/git/cnode/node_modules/mongoose/node_modules/mongodb/lib/mongodb/connection/server.js:379:22) at EventEmitter.emit (events.js:95:17) at null.<anonymous> (/home/www/git/cnode/node_modules/mongoose/node_modules/mongodb/lib/mongodb/connection/connection_pool.js:136:13)