I have read Why would Bitcoin-QT attempt to charge a processing fee, when I have my transaction fees set to zero? but I still have a question.
I am sending 0.01 BTC from my wallet to my Ethereum intermediate address and then back again, so as to verify recoverability.
Sending 0.01 BTC worked fine without transaction fees. When sending it back I get "The total exceeds your balance when the 0.0001 BTC transaction fee is included." although fees are set to zero.
Why is there a fee requirement in one direction only?