Why Is My EA Not Trading? A 12-Point MT5 and MT4 Checklist

Short answer: most EAs that "won't trade" are switched off, not broken. Check the terminal's Algo Trading (AutoTrading) button, the EA's own "Allow Algo Trading" box, and the Experts and Journal tabs for an error code. If there is no error, the EA is probably running correctly and its conditions have simply not been met.

Work down this list in order — it is sorted by how often each cause turns out to be the answer.

1. Algo Trading is switched off

MT5's toolbar button is Algo Trading (AutoTrading in MT4 and older MT5 builds). If it is off, every EA on the terminal runs but cannot trade. Error: MT5 retcode 10027 (client disabled algo trading); MT4 error 4109.

2. The EA itself is not allowed to trade

Right-click the chart → Expert Advisors → Properties → Common, and tick Allow Algo Trading (MT4: "Allow live trading"). This setting is per chart.

3. You logged in with the investor password

An investor (read-only) login can see the account but cannot place orders. Log in with the master password.

4. The broker disabled EAs on the account

Some account types disallow automated trading entirely. Retcode 10026 means the server disabled it. An EA can read this directly — in TradeSmithy, an Account Info node set to EA trading allowed returns whether EAs may trade here.

5. There is an error you have not looked at

Open the Toolbox (Ctrl+T) and read the Experts and Journal tabs. The common retcodes:

MT5 retcode	MT4 error	Meaning	Usual fix
10014	131	Invalid volume	Lot below minimum or not a multiple of the lot step
10016	130	Invalid stops	Stop or target closer than the broker's minimum distance
10018	132	Market closed	Wait, or check the symbol's trading hours
10019	134	Not enough money	Smaller lot, or more margin
10030	—	Unsupported filling mode	Do not hardcode a filling mode
10017	133	Trading disabled for the symbol	Check the symbol's trade mode

6. The symbol name does not match

EURUSD and EURUSD.m are different symbols. An EA with a typed-in symbol name does nothing on a broker that uses suffixes. Use the chart's own symbol.

7. The lot size is invalid for this symbol

Every symbol has a minimum lot, a maximum and a step. 0.015 on a 0.01-step symbol fails. Read the limits from the symbol — Symbol Info exposes Minimum lot, Maximum lot and Lot step — and round to them.

8. The stops are too close

Brokers set a minimum distance between price and any stop or target (the stops level). A 5-point stop on a symbol with a 30-point stops level is rejected. We cover this error fully in a later post on invalid stops.

9. The conditions have not happened yet

The most common cause when there is no error. An RSI strategy waiting for 30 may wait days on H4. Add a Print of the values, or watch the indicator on the chart, before assuming a bug.

10. It only checks once per candle

EAs that act on a new candle do nothing between closes. On H4 that is up to four hours of silence, by design.

11. It thinks it already has a trade

"One position at a time" logic counts existing positions. If it counts every position on the account rather than only its own — no magic-number filter — your manual trade blocks it.

12. It works in the tester but not live

Usually settings 1–4, a symbol suffix, or spread: a spread filter that passes in the tester's fixed spread fails at the live rollover spread.

Build EAs that tell you why

Many of these failures are preventable in the strategy itself: read lot limits and stop distance from the symbol, filter positions by the EA's own trades, and check whether automated trading is allowed before trying. TradeSmithy's Symbol Info, Account Info and Positions & Orders nodes put those values in the graph. Start free and build it in, or compare approaches in our EA builder comparison. New to EAs? Start with what an Expert Advisor is.

Frequently asked questions

Why is my EA not opening trades in MT5?

Most often Algo Trading is off, the EA is not allowed to trade on that chart, or its conditions have not been met. Check the Experts tab for an error.

What does error 10027 mean?

Automated trading is disabled in the client terminal. Switch on the Algo Trading button.

My EA works in the Strategy Tester but not on a live account — why?

The tester ignores the terminal's trading switches and account permissions, and uses fixed conditions. Check permissions, symbol name and spread.

Why did my EA stop trading after a restart?

Algo Trading may have been switched off, or the EA was removed from the chart profile. Reattach it and check both switches.