How to add indicators to MT4 (and MT5): step-by-step guide

Q: What is the difference between .ex4 and .mq4 files?

An.ex4 file is a compiled program that MT4 can run as it is. An.mq4 file is the readable MQL4 source code. MT4 compiles an.mq4 automatically when it loads it, or you can open it in MetaEditor and click Compile. Most commercial indicators ship only as.ex4, so the code cannot be read or changed. If an.mq4 fails to compile, it will not attach to a chart until the errors are fixed.

You bought or downloaded an indicator, you have a file called something like SupplyZones.ex4, and MT4 acts as if it does not exist. Double-clicking the file does nothing useful. Dragging it onto the chart does nothing either. The platform wants the file in one specific folder, and it never tells you which one.

This guide covers how to add indicators to MT4 step by step, the MT5 equivalent, what changes when you buy through the MQL5 Market, and the honest answer for the mobile apps. The last section is a troubleshooting table for when the indicator still refuses to show up.

Key Findings

One folder does the work: File > Open Data Folder > MQL4 > Indicators is where every MT4 custom indicator has to live.
Refresh, then drag: after copying, refresh the Navigator or restart MT4, then drag the indicator onto a chart.
Platforms do not mix: .ex4 runs only on MT4 and .ex5 only on MT5.
Mobile is closed: the MT4 and MT5 phone apps cannot load custom indicators at all.

How do you add indicators to MT4?

To add an indicator to MT4, open File > Open Data Folder, go into MQL4 > Indicators, and paste the indicator file there. Back in MT4, right-click Indicators in the Navigator and choose Refresh, or restart the terminal. Then drag the indicator from the Navigator onto your chart and click OK.

That covers custom indicators, the ones you download or buy. The built-in ones (Moving Average, RSI, MACD and the rest) are already in Insert > Indicators and need no install. If you are still choosing which tools deserve a place on the chart, start with the best trading indicators for MT4, MT5 and TradingView and the wider list of forex indicators.

How to add indicators to MT4, step by step

These steps work for all MetaTrader 4 custom indicators, free or paid. Our own installation guide for RelicusRoad Pro follows the same path.

1. Get the right file

You need a file ending in .ex4 or .mq4. If the download is a .zip, extract it first. MT4 cannot read a zip. Some packages include extra folders, such as a Libraries or Files folder; those go into the matching folders inside MQL4, not into Indicators.

2. Open the data folder

In MT4, click File > Open Data Folder. Windows Explorer opens the folder that belongs to this exact terminal. Do not browse to Program Files yourself. Modern MT4 builds keep indicators in a per-user folder under AppData, and each broker’s MT4 has its own one.

3. Paste the file into MQL4\Indicators

Open MQL4, then Indicators, and paste the file. If Windows marks downloaded files as blocked, right-click the file, open Properties, and tick Unblock. A blocked file is one of the quieter reasons an indicator fails to load.

4. Refresh the Navigator or restart MT4

Open the Navigator with View > Navigator (Ctrl+N). Right-click Indicators and choose Refresh. If the name still does not appear, close and reopen MT4. A restart is the safer habit, and it is what our install guide recommends.

5. Drag it onto a chart

Open the chart you want, then drag the indicator from the Navigator onto it. Double-clicking the name, or right-clicking it and choosing Attach to a chart, does the same thing. The official MetaTrader 4 help lists all three methods and notes that a settings window opens as soon as you attach one.

6. Check the Common and Inputs tabs

The settings window usually has Common, Inputs, Colors and Levels tabs. Inputs holds the indicator’s own settings, such as periods, alert switches and styles. Common holds the Allow DLL imports box.

Leave DLL imports off unless the tool needs it and you trust where it came from. A DLL runs outside MT4’s sandbox with broad access to your machine. Some licensed tools use one for activation, but an unknown free download that asks for DLL access deserves suspicion. We cover more of these trade-offs in the risks of custom indicators.

7. Save a template

Once the chart looks right, right-click it and choose Template > Save Template. Next time, one click loads every indicator with the same settings. If you save the template as default, MT4 applies it to every new chart you open.

.ex4 or .mq4: which file do you need?

Either works. An .ex4 is a compiled program that MT4 runs as it is. An .mq4 is the readable MQL4 source code, which MT4 compiles into an .ex4 when it loads it. Most paid indicators ship as .ex4 only, so the seller’s code stays private.

If you have an .mq4, you can also open it in MetaEditor (press F4 in MT4) and click Compile. Watch the errors panel at the bottom. According to MetaTrader 4’s own documentation, an indicator compiled with errors cannot be attached to a chart at all. Old free indicators written for much older MT4 builds often trip on this. Warnings are fine; errors are not.

How do you install an indicator in MT5?

Installing an indicator in MT5 follows the same steps with different names. Open File > Open Data Folder, go into MQL5 > Indicators, and paste the .ex5 or .mq5 file. Refresh the Navigator or restart MT5, then drag the indicator onto a chart.

The one trap is mixing platforms. An .ex4 file will not run on MT5, and an .ex5 will not run on MT4. MQL4 source code usually will not compile as MQL5 without changes either. If you run both terminals, get both builds from the seller. The MT5 indicators guide goes into what is worth installing there, and the non-repaint MT5 indicators guide shows how to check a new tool once it is on the chart.

What about indicators bought on the MQL5 Market?

Indicators bought or rented in the MQL5 Market install themselves. You buy from the Market tab inside MT4 or MT5 while logged in to your MQL5.community account, and the terminal downloads the indicator into Navigator > Indicators > Market. There is no file to copy, and it appears there ready to drag onto a chart.

Two things differ from a manual install. The purchase is tied to your MQL5 account, and each purchase allows a set number of activations on new computers or terminals, fixed by the seller. So reinstall from the Market tab rather than copying the file around. Market files are also protected, and copying one into another terminal’s Indicators folder will not work.

Can you add custom indicators to MT4 or MT5 mobile?

No. The MT4 and MT5 apps for iPhone and Android cannot load custom indicators. There is no folder to paste into and no import option. The apps run only their built-in set. The MetaTrader 5 iPhone help lists 30 built-in indicators and nothing else.

That answers most searches for MT4 mobile custom indicators and MetaTrader mobile custom indicators, however they are phrased. If you need a custom tool on your phone, you have three realistic routes:

Use a platform whose app runs it. TradingView indicators work on its mobile app, so a tool sold in a TradingView version travels with you. That is the reason some traders want one indicator on three platforms.
Run desktop MT4 on a VPS. A forex VPS keeps the terminal and its indicators running, and you can reach it by remote desktop from your phone.
Send alerts to your phone. Many indicators can send push notifications to the MetaTrader app through your MetaQuotes ID (set in Tools > Options > Notifications). The chart stays on your PC; the signal reaches your pocket.

Custom indicator not showing in MT4? Fixes for common problems

Most failures trace back to the folder, the file type, or a blocked permission. Check the Experts and Journal tabs in the Terminal window (Ctrl+T) first, because MT4 usually logs the reason there.

What you see	Likely cause	Fix
Indicator not in the Navigator	File in the wrong terminal’s folder, or still zipped	Use File > Open Data Folder from the terminal you trade on, extract the zip, then refresh
Name appears, but nothing happens on drag	Compile errors in an .mq4, or a blocked download	Compile in MetaEditor and fix errors; Properties > Unblock; restart MT4
“Cannot load indicator”	File blocked, corrupted, or built for the other platform	Unblock it, download it again, check .ex4 vs .ex5
“DLL calls are not allowed” in Experts	Allow DLL imports is off	Tick it on the Common tab (or Tools > Options > Expert Advisors) for trusted tools only
Indicator loads but draws nothing	Not enough chart history, or wrong inputs	Scroll back to load more bars, check Inputs, try another timeframe
Only shows on one chart	It was attached to that chart only	Save a template and apply it, or save as `default`

Indicator not in the Navigator

Likely cause: File in the wrong terminal’s folder, or still zipped
Fix: Use File > Open Data Folder from the terminal you trade on, extract the zip, then refresh

Name appears, but nothing happens on drag

Likely cause: Compile errors in an .mq4, or a blocked download
Fix: Compile in MetaEditor and fix errors; Properties > Unblock; restart MT4

“Cannot load indicator”

Likely cause: File blocked, corrupted, or built for the other platform
Fix: Unblock it, download it again, check .ex4 vs .ex5

“DLL calls are not allowed” in Experts

Likely cause: Allow DLL imports is off
Fix: Tick it on the Common tab (or Tools > Options > Expert Advisors) for trusted tools only

Indicator loads but draws nothing

Likely cause: Not enough chart history, or wrong inputs
Fix: Scroll back to load more bars, check Inputs, try another timeframe

Only shows on one chart

Likely cause: It was attached to that chart only
Fix: Save a template and apply it, or save as default

If an indicator draws signals that later move or vanish, that is a different problem: repainting, not installation. The non-repaint MT4 indicator guide shows how to test for it before you trade on it. Two small tools that are good first installs to practice on are an MT4 clock indicator and an MT4 crosshair setup.

Where RelicusRoad Pro fits

RelicusRoad Pro installs exactly as described above. On MT4 and MT5 it goes into the Indicators folder, or installs itself when bought through the MQL5 Market. Direct plans include the TradingView version under the same license, which is also the answer if you want the same levels on your phone. The full walkthrough, including license activation, is in our installation guide.

Frequently asked questions

How do I add a custom indicator to MT4?

In MT4, click File > Open Data Folder, open MQL4, then Indicators, and paste your .ex4 or .mq4 file there. Go back to MT4, right-click Indicators in the Navigator window and choose Refresh, or restart the terminal. The indicator now appears under Indicators in the Navigator. Drag it onto a chart, check the settings window that opens, and click OK.

Why is my custom indicator not showing in MT4?

The usual cause is the wrong folder. Each MT4 installation has its own data folder, so a file copied into one broker’s terminal will not appear in another. Also check that the file sits directly in MQL4\Indicators rather than inside a zip or a subfolder you did not expect, that Windows has not blocked the download (file Properties > Unblock), and that you refreshed the Navigator or restarted MT4 after copying.

Can you add custom indicators to MT4 mobile?

No. The MT4 and MT5 apps for iPhone and Android run only the indicators built into the app, and there is no folder or import option for .ex4 or .ex5 files. If you need a custom tool on your phone, the realistic options are a version of the tool built for a platform whose mobile app supports it, such as TradingView, or running desktop MT4 on a VPS and sending its alerts to your phone as push notifications.

What is the difference between .ex4 and .mq4 files?

An .ex4 file is a compiled program that MT4 can run as it is. An .mq4 file is the readable MQL4 source code. MT4 compiles an .mq4 automatically when it loads it, or you can open it in MetaEditor and click Compile. Most commercial indicators ship only as .ex4, so the code cannot be read or changed. If an .mq4 fails to compile, it will not attach to a chart until the errors are fixed.

How do I install an indicator in MT5?

The steps match MT4 with different names. Click File > Open Data Folder, open MQL5, then Indicators, and paste your .ex5 or .mq5 file there. Refresh the Navigator or restart MT5, then drag the indicator from Navigator > Indicators onto a chart. Indicators bought in the MQL5 Market skip all of this and install themselves. An MT4 file (.ex4) will not work in MT5; you need the MT5 build of the indicator.

What does Allow DLL imports mean in MT4?

It lets the indicator call functions in external Windows libraries (.dll files) outside MT4’s own sandbox. Some legitimate tools need it for things like licensing or extra data feeds. It also gives the code wide access to your computer, so only tick it for indicators from a source you trust. If a tool needs it and the box is off, the Experts tab shows a message that DLL calls are not allowed and the indicator stops working.

Want one indicator you install once per platform and can still check on your phone? RelicusRoad Pro runs on MT4, MT5 and TradingView under a single direct license.