Hi, <br>I am doing a program that use asio to construct a timer thread. The thread use asio to async_wait many timers. These timers are constructed &nbsp;by boost::asio::system_timer. These timers are mostly designed to fire only once. When they are fired or canceled, I put them to a free queue to reuse.<br><br>But when I reuse these times, I called expire_from_now() and async_wait() again on the timer, I got the timer fired immediately with error_code set to "ec == boost::asio::error::operation_aborted". And the timer are not fired after like 5 seconds late as I set to expire_from_now(seconds(5)). <br><br>How to reuse the timer correctly?<br><br>My codes basically are as follows:<br><br>m_timer.cancel(); &nbsp; &nbsp; // I tried to cancel the timer first, but no use, I still get the timer fired at once<br>m_timer.expires_from_now(std::chrono::seconds(nInterval));<br>m_timer.async_wait(boost::bind(&amp;qmInnerTimer::Fire, this, _1));<br><br><br>Thanks.<br>-Bruce<br>