The error “Market is closed. Any trading functionality is not available” indicates the strategy tried to trade while the market was closed.
This can happen because strategies can be in running even when the market is closed. This is quite normal for a strategy to be running right through the weekend and this is not a problem as typically a strategy only actions on price updates. However, FXCM sometimes update market data while the market is still non-tradeable. This is very common in the hour or so before market opens each week.
The following is taken from FXCM’s Trading Execution Risks document.
PRICES UPDATING BEFORE THE OPEN
Shortly prior to the open, the Trading Desk refreshes rates to reflect current market pricing in preparation for the open. At this time, trades and orders held over the weekend are subject to execution. Quotes during this time are not executable for new market orders. After the open, traders may place new trades, and cancel or modify existing orders.
If the prices start updating while the market is still closed, a running strategy will see market updates and if the conditions are favorable, try to trade resulting in the above mentioned error.
If the strategy has handled this scenario properly, it should not negatively impact the strategy. It is also possible to develop countermeasures to avoid this scenario completely but according to FXCM there is no full-proof way to do this. For more information, see the following link on DailyFX: http://www.dailyfx.com/forex_forum/signal-strategy-fxcm-marketscope/622674-non-tradable-hours.html