I also posted this on the NEM forum.
I've tried twice to send XEM to Polo, but the transactions remain on pending and after one hour they time out.
What can I do about this?
I have the latest client (of course), blockchain is synched, my accounts are added correctly.
are you adding the unique message?
Yes, I do. The transaction never gets picked up by the blockchain.
Also, have you contacted Poloniex?
The transaction never leaves my wallet, so there isn't anything Poloniex can do about that.
Please check your system time and see if it's way off.