How to Install an EA or Indicator on MT4 & MT5

Installing an expert advisor (EA) or custom indicator on MetaTrader takes about five minutes once you know where the files go. This guide covers both MetaTrader 4 and MetaTrader 5, plus the settings that trip up most first-timers.

Before you start

You'll have a file ending in .ex4 or .mq4 (MT4) or .ex5 or .mq5 (MT5). Indicators and EAs install the same way but go in different folders.
Always test on a demo account first. Never put a brand-new EA on a live account before you understand how it behaves.

Step 1 — Open the data folder

In MetaTrader, click File → Open Data Folder. This opens the hidden folder where MetaTrader keeps your add-ons. Don't try to find it manually — this menu always opens the correct one.

Step 2 — Drop the file in the right place

Inside the data folder, open the MQL4 folder (MT4) or MQL5 folder (MT5), then:

Expert advisors go in MQL4/Experts or MQL5/Experts.
Indicators go in MQL4/Indicators or MQL5/Indicators.

Paste your file into the matching folder.

Step 3 — Restart MetaTrader

Close and reopen the platform (or right-click the Navigator panel and choose Refresh). Your EA or indicator now appears in the Navigator panel on the left, under Expert Advisors or Indicators.

Step 4 — Enable AutoTrading (EAs only)

Click the AutoTrading button in the toolbar so it turns green. Without this, an EA will load but never place trades.

The #1 beginner mistake: a smiley face but no trades. If the chart shows a sad face or an X in the top-right corner, AutoTrading is off or the EA isn't allowed to trade. Turn on AutoTrading and, in Tools → Options → Expert Advisors, tick "Allow algorithmic trading".

Step 5 — Attach it to a chart

Open a chart for the pair and timeframe the tool is designed for, then drag the EA or indicator from the Navigator onto the chart. In the dialog that appears, check "Allow Algo Trading" and set your inputs, then click OK.

Step 6 — Confirm it's running

A smiley face in the top-right of the chart means the EA is active. Watch the Experts and Journal tabs at the bottom for messages — that's where the EA tells you what it's doing or what's wrong.

Common problems

Symptom	Fix
EA not in Navigator	Wrong folder, or restart needed. Re-check Experts vs Indicators folder.
Sad face on chart	Enable AutoTrading and "Allow algorithmic trading" in options.
No trades placed	Check the Journal for errors; confirm the EA's pair/timeframe and that the market is open.
"DLL not allowed"	Some EAs need DLL imports enabled in the EA's settings — only enable for tools you trust.

Need an account to test on? Any MT4/MT5 broker works. You can open a free demo with Exness or Deriv to try tools risk-free. (Affiliate links — disclosure.)

That's it. Once you've done it once, every future EA or indicator follows the same six steps.