Quote from: okbaby123 on October 21, 2016, 11:09:17 AM

I try to broadcast a trans with locktime

But when I set the locktime which is later than current time it is failed to broadcast

And sent it earlier than current time (or block) it works , but it doesn't make sense, if so.

Anyone can help.

To the mannul https://bitcoin.org/en/developer-guide#locktime-and-sequence-number

It should work.

Check out, these, they may explain it better:

http://bitcoin.stackexchange.com/questions/26937/nlocktime-transactions-how-do-they-persist-are-they-broadcast-before-they-are
And:
https://bitcointalk.org/index.php?topic=23501.0

Particularly: "In other words: the responsibility of keeping a copy of the transaction and broadcast that when it's time, lies with whoever is interested in making the transaction (probably the recipient)"

In short, you broadcast after the lock time.