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Automation · Expert Advisors

How to Install an EA on MT4

To install an EA on MT4, open File ▸ Open Data Folder, drop your .ex4 or .mq4 file into MQL4/Experts, restart MT4, then drag the EA onto a chart, tick 'Allow live trading', and switch on AutoTrading. A smiley face means it's running. Here's each step — and test it first.

By Marcus Hale, Automation & Strategy Writer

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Installing an Expert Advisor takes a couple of minutes on the desktop terminal (mobile can't run EAs). The key: EAs live in the MQL4/Experts folder — distinct from custom indicators, which go in MQL4/Indicators. Get the folder right, enable AutoTrading, and confirm the smiley face.

Install the EA, step by step

  1. Open the MT4 Data Folder

    In MetaTrader 4, click File ▸ Open Data Folder. This opens the correct location for your platform's files — don't guess the install path.

  2. Open MQL4 ▸ Experts and add your file

    Double-click the MQL4 folder, then Experts, and copy your EA file (.ex4 or .mq4) into the Experts folder.

  3. Restart MT4 or refresh the Navigator

    Close and reopen MT4, or right-click 'Expert Advisors' in the Navigator and choose Refresh. Your EA now appears under Navigator ▸ Expert Advisors.

  4. Attach the EA to a chart

    Open a chart, then drag the EA from the Navigator onto it. In the dialog's Common tab, tick Allow live trading (and 'Allow DLL imports' only if the EA requires it), then click OK.

  5. Enable the AutoTrading button

    Click the AutoTrading button in the top toolbar so it's on. A smiley face in the top-right of the chart confirms the EA is active; a sad face means AutoTrading is off or live trading wasn't allowed.

Enable AutoTrading (and DLL imports only if required)

Two switches must be on for an EA to trade: the per-chart Allow live trading checkbox and the global AutoTrading toolbar button. If an EA's documentation says it needs external libraries, also tick Allow DLL imports — but only when required, since DLLs can run arbitrary code.

How to tell the EA is running

  • Smiley face (top-right of the chart) = EA attached and AutoTrading on (running).
  • Sad face = AutoTrading is off, or "Allow live trading" wasn't ticked.
  • Check the Terminal ▸ Experts tab for the EA's activity log.
Installing an EA isn't the same as having a profitable one

Before any EA trades real money, backtest it in the Strategy Tester and forward-test on a demo. Automated trading is high-risk and most retail traders lose money.

Test your EA on a free demo first

Pepperstone offers EA-friendly raw-spread execution and a free MT4 demo — set up your EA, test it, and only go live when you're ready.

See Pepperstone → What are Expert Advisors?

⚠ Trading forex and CFDs is high-risk and most retail traders lose money. This is not financial advice.

Affiliate disclosure: we may earn a commission if you open a broker account through our links, at no extra cost to you. Learn more.

Next steps

Learn the Strategy Tester to backtest, run your EA 24/5 on an MT4 VPS, or compare it with installing an indicator (different folder, different flow). EA won't run? See MT4 not working.

Frequently asked questions

Where do I put an EA file in MT4?

Put it in the MQL4/Experts folder. Open it via File ▸ Open Data Folder, then go into MQL4 ▸ Experts and copy your .ex4 or .mq4 file there. Restart MT4 or refresh the Navigator and the EA appears under Expert Advisors.

Why isn't my EA showing in the Navigator?

Usually the file is in the wrong folder or the Navigator wasn't refreshed. Confirm the EA is in MQL4/Experts (not Indicators), then restart MT4 or right-click 'Expert Advisors' ▸ Refresh. Only .ex4/.mq4 Expert files appear there.

Why does my EA show a sad face?

A sad face means the EA isn't allowed to trade. Open the chart's EA settings and tick 'Allow live trading', then switch on the AutoTrading toolbar button. When both are on, the icon becomes a smiley face and the EA can place trades.

Do I need to allow DLL imports for every EA?

No. Only tick 'Allow DLL imports' if the EA's own instructions say it needs external libraries. DLLs can run arbitrary code, so leave the option off for EAs that don't require it. Most simple EAs work without it.

Can I install an EA on MT4 mobile?

No. The MT4 Android and iOS apps don't support Expert Advisors — EAs run only on the desktop terminal. To keep an EA running when your computer is off, install it on desktop and host it on a VPS.

Trading foreign exchange and contracts for difference (CFDs) carries a high level of risk and may not be suitable for all investors. Leverage can work against you as well as for you. You could lose some or all of your deposited funds; do not trade with money you cannot afford to lose. Past performance is not indicative of future results. Nothing on MT4Download.com is financial, investment, or trading advice. Consider your circumstances and seek independent advice if needed.