EA not trading, sad smiley face in MetaTrader 4

What is causing it

AutoTrading is off, or the EA is not allowed to trade.

Why this happens

MT4 puts more than one switch between an Expert Advisor and your account, because code that can place live orders is the most consequential thing the platform runs. There is a terminal-wide permission in the options, a toolbar toggle that acts as an instant master switch, and a per-EA permission on the Common tab of its properties. Any one being off blocks trading, and the chart shows the same sad face in every case without saying which.

Reading the face correctly saves time. A frowning face means the EA is attached and running its logic but is not permitted to send orders, so it can sit there for hours doing its calculations while placing nothing. That is a different situation from an EA that failed to load at all, which would not show a face on the chart.

The fix, step by step

1. Click the AutoTrading button in the toolbar so it is green.
2. Open Tools, Options, Expert Advisors and tick "Allow automated trading".
3. On the EA, press F7 and tick "Allow live trading" on the Common tab.
4. Confirm the face becomes a happy smiley.

How to confirm it is fixed

The face in the top right of the chart should be smiling and the toolbar AutoTrading button should show as enabled. Open the Experts tab: a permitted EA logs its initialisation and its activity there, while a blocked one logs an entry about trading not being allowed. The real proof is the EA acting when its conditions are next met.

Stopping it happening again

Check the toolbar toggle every time you start the terminal, since it does not reliably survive a crash or restart in the state you left it. On a VPS, check the face after any reboot. Leaving the terminal-level permission on and using the toolbar button as your daily control is the practical arrangement.