How to Install a Forex EA on MT4 & MT5

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Complete Self-Service MT4 & MT5 Guide

Nexus Forex EA Installation & Setup Guide

This guide is designed so a Nexus client can complete the installation without needing someone to remote into the computer. Work through it in order for EURUSD and GBPUSD on either MetaTrader 4 or MetaTrader 5, validate everything on demo for at least 4–6 weeks, and use the troubleshooting section if something does not look right.

Security First — Nexus Never Needs Your Trading Password For licence verification or technical support, provide only the broker, platform and trading account number requested. Never email Nexus your broker password, MetaTrader master password, investor password, bank login, card information or VPS password.
Before You Start

Have These Items Ready

Most installation issues happen because the wrong platform, wrong account, wrong file or wrong preset is used. Check these first.

Active Nexus licence
Licensed trading account number
Correct broker name and server
MT4 or MT5 platform matching your licence
Current Nexus EA file supplied by Nexus
Current EURUSD / GBPUSD preset files
Windows PC or Windows VPS
Licensed demo account for initial validation
Existing Nexus Screenshot — Account Number Where to find the MetaTrader trading account number
Your trading account number is the identifier used for licence verification. Do not send your trading password.
Step 01

Set Up and Connect to Your VPS

Recommended for keeping MetaTrader and Nexus running independently of your home computer.

1A — Obtain Your VPS Details

Save the IP Address, Username and VPS Password

Your VPS provider normally emails these details after the server is created. They are credentials for the remote Windows server — not your broker account.

Existing Nexus Screenshot Example VPS server ready email containing IP address and login details
Example of the server-ready information supplied by a VPS provider.
1B — Open Remote Desktop

Connect From Windows

  1. Click Windows Start.
  2. Type Remote Desktop Connection.
  3. Open the application.
  4. Enter the VPS IP address in the Computer field.
  5. Click Connect.
  6. Enter the VPS username and password supplied by the provider.
Existing Nexus Screenshot — Find Remote Desktop Searching Windows for Remote Desktop Connection
Search Windows for Remote Desktop Connection.
Existing Nexus Screenshot — Connect Remote Desktop Connection IP address field
Enter the VPS IP address, then connect.
When You Finish Working on the VPS Close or disconnect the Remote Desktop window. Do not shut down Windows or power off the VPS, because MetaTrader must continue running.
1C — Prepare Windows

Reduce the Risk of MetaTrader Being Left Offline

  • Install outstanding Windows updates before starting demo or live operation.
  • Set appropriate Windows active hours so restarts are less likely during your normal monitoring period.
  • Do not configure the VPS to sleep.
  • Optionally place an MT4 or MT5 shortcut in the Windows Startup folder using Win + R → shell:startup.
  • After any VPS restart, Windows update or server maintenance, manually confirm MetaTrader reopened, connected and Nexus is active.
Recommended Daily VPS Check Even when using a VPS, check the platform at least once each morning. Confirm MT4/MT5 is open, connected to the broker, automated trading remains enabled and the Nexus EA is still attached to the correct chart.
Step 02

Install Your Broker's MT4 or MT5 Platform

The platform must match both your broker account and the Nexus build issued to you.

  1. While connected to the VPS, open your broker's official website or client portal.
  2. Download MetaTrader 4 for an MT4 Nexus licence or MetaTrader 5 for an MT5 Nexus licence.
  3. Run the installer and open MetaTrader.
  4. Choose File → Login to Trade Account.
  5. Enter the account number, your private trading password and the exact assigned broker server.
  6. Confirm prices begin updating and the connection status is active.
Existing Nexus Screenshot — Connected Platform MetaTrader connected to broker account with connection indicator
MT4 example: a connected terminal shows active broker connectivity and updating prices.
MT5 Visual Reference — Login to Trade Account

MT5 uses File → Login to Trade Account. Enter the account number, password and server supplied by your broker.

Open Official MetaTrader 5 Login Guide ↗
No Connection? Recheck the exact broker server. A correct account number with the wrong server can still fail to connect.
Step 03

Copy Your Nexus Files to the VPS

Keep the current EA and preset files together so you do not accidentally load an older version.

  1. Download the current Nexus package supplied to you.
  2. Copy the files onto the VPS desktop.
  3. Do not rename the files unless Nexus specifically instructs you to.
  4. Do not mix old and new preset files in the same working folder.
Existing Nexus Screenshot — Files on VPS Nexus EA and preset files copied to VPS desktop
Place the current Nexus EA and preset files somewhere easy to locate during installation.
Step 04 — MT4

Install Nexus Into MetaTrader 4

Skip this step if your Nexus licence is for MT5.

4A — Open the MT4 Data Folder

Copy the .ex4 File Into MQL4 → Experts

  1. In MT4 click File → Open Data Folder.
  2. Open MQL4.
  3. Open Experts.
  4. Copy the current Nexus .ex4 file into that Experts folder.
  5. Return to MT4.
  6. In Navigator, right-click Expert Advisors and select Refresh.
  7. If Nexus still does not appear, close and reopen MT4.
Existing Nexus Screenshot — MT4 Navigator Nexus EA visible in MetaTrader 4 Expert Advisors Navigator
After a successful installation, Nexus appears under Expert Advisors in Navigator.
Step 05 — MT5

Install Nexus Into MetaTrader 5

Skip this step if your Nexus licence is for MT4.

5A — Open the MT5 Data Folder

Copy the .ex5 File Into MQL5 → Experts

  1. Open MT5.
  2. Click File → Open Data Folder.
  3. Double-click MQL5.
  4. Double-click Experts.
  5. Copy the Nexus MT5 .ex5 file into the Experts folder.
  6. Return to MT5.
  7. Open Navigator with Ctrl+N if it is not already visible.
  8. Expand Expert Advisors.
  9. Right-click the Expert Advisors area and refresh, or restart MT5 if Nexus does not immediately appear.
Do Not Use the MT4 File in MT5 MT4 and MT5 use different compiled EA formats. An .ex4 file is for MT4; the MT5 build is normally an .ex5 file.
MT5 Visual Reference — File → Open Data Folder

MetaQuotes confirms that File → Open Data Folder provides quick access to MT5's application data directories, including MQL5.

Open Official MT5 Data Folder Guide ↗
5B — What You Should See

Confirm Nexus Appears in Navigator

  • Navigator should show an Expert Advisors section.
  • Nexus should appear beneath Expert Advisors after the correct file is installed.
  • If the EA is missing, verify the exact data folder rather than manually browsing to an unrelated MetaTrader installation directory.
  • If you were supplied source code rather than a compiled file, do not attempt to modify or compile it unless Nexus specifically instructed you to do so.
MT5 Visual Reference — Navigator & Expert Advisors

The MT5 Navigator contains trading robots and is used to launch/manage Expert Advisors.

Open Official MT5 Interface Guide ↗
Step 06

Open the Correct EURUSD or GBPUSD Chart

Nexus EURUSD and GBPUSD use different chart timeframes.

Required Nexus Chart Settings The current Nexus pair settings are: GBPUSD = 5 Minute Chart (M5) and EURUSD = 15 Minute Chart (M15). Attach each EA only to the correct currency pair and timeframe.
GBPUSD M5 5 Minute Chart
EURUSD M15 15 Minute Chart
  1. Open Market Watch.
  2. Locate EURUSD or GBPUSD.
  3. If you cannot see the pair, right-click Market Watch and show the required symbol.
  4. Open a new chart for the required pair.
  5. For GBPUSD, select M5 — 5 Minute.
  6. For EURUSD, select M15 — 15 Minute.
  7. Confirm the symbol name and timeframe before attaching Nexus.
Existing Nexus Screenshot — MT4 Timeframe Example Selecting a chart timeframe in MetaTrader
Select M5 for GBPUSD and M15 for EURUSD before attaching the Nexus EA.
Broker Symbol Suffixes Your broker may display symbols such as EURUSD.a, EURUSDm or another suffix. Use the tradable symbol provided by your broker and contact Nexus if you are unsure about compatibility.
Do Not Put the EA on the Wrong Timeframe GBPUSD Nexus should run on M5. EURUSD Nexus should run on M15. Incorrect chart settings may materially change how the EA evaluates trading conditions.
Step 07

Attach Nexus to the Chart

Drag the EA from Navigator onto the matching pair chart.

  1. Expand Expert Advisors in Navigator.
  2. Locate the Nexus EA.
  3. Drag it onto the correct EURUSD or GBPUSD chart.
  4. Confirm GBPUSD is M5 or EURUSD is M15.
  5. The EA properties/settings window should open.
  6. Do not click OK until permissions and the preset are checked.
Existing Nexus Screenshot — MT4 Navigator Dragging Nexus EA from MetaTrader Navigator
MT4 example: drag Nexus from Expert Advisors onto the correct chart.
Step 08

Check Trading Permissions

Platform-level automation and EA-level permission must both allow trading.

8A — MT4 Permissions

Common Tab

  • Confirm Allow live trading is enabled.
  • Only enable DLL imports if your current Nexus build specifically requires them.
  • Do not enable unrelated options simply because an older screenshot shows them.
Existing Nexus Screenshot — MT4 Common Tab MT4 Expert Advisor Common tab trading permissions
MT4 example of EA permissions. Follow the permissions specified with your current Nexus build.
8B — MT5 Permissions

Check Global and Individual EA Automation

  1. On the main MT5 toolbar, make sure Algo Trading is enabled.
  2. Open Tools → Options → Expert Advisors.
  3. Confirm automated trading is globally permitted.
  4. Review any options that disable automated trading after an account, profile, symbol or timeframe change.
  5. In the Nexus EA properties, confirm the individual EA is allowed to trade.
  6. Enable DLL imports only if the current Nexus MT5 package explicitly requires them.
MT5 Visual Reference — Expert Advisor Settings

MetaQuotes documents the global Expert Advisor settings under Tools → Options → Expert Advisors, including the platform-wide automated-trading permission.

Open Official MT5 EA Settings Guide ↗
MT5 Visual Reference — Controlling Individual EAs

MT5 can control trading at both platform level and for each running Expert Advisor. Both must permit trading.

Open Official MT5 Automated Trading Guide ↗
Step 09

Load the Correct Nexus Preset

Use the preset supplied for the exact pair, platform and risk profile.

Conservative Recommended for first demo validation.
Moderate Higher risk than Conservative.
Aggressive Highest risk profile.
  1. Open the EA's Inputs tab.
  2. Click Load.
  3. Browse to the folder containing the current Nexus presets.
  4. Select the preset for the correct pair and risk profile.
  5. After loading, visually confirm the Inputs values changed.
  6. Do not manually alter technical parameters unless you understand them or Nexus support instructed you to do so.
Existing Nexus Screenshot — Inputs Tab MetaTrader EA Inputs tab with Load button
Open Inputs and click Load.
Existing Nexus Screenshot — Select Preset Selecting a Nexus preset file
Select the current preset supplied for the correct Nexus pair and configuration.
Best Starting Point Use Conservative for first-time demo validation unless your current Nexus documentation specifically instructs otherwise.
Step 10

Set and Review Your Lot Size Carefully

Lot size has a direct effect on risk. Start small and increase only after you understand the EA's behaviour.

Use an appropriate lot-size calculator based on your trading balance, account type, broker conditions and available margin to determine an appropriate lot size. Keep your lot sizes very low at the beginning. Only consider increasing position size once you are well versed in the EA's behaviour and comfortable with the level of drawdown and risk being taken.

Your Lot Size Must Match Your Own Risk Tolerance Never increase lot size simply because recent performance has been positive. Larger lot sizes increase both potential gains and potential losses. Always make sure your chosen lot size is consistent with your own risk settings, account balance and available margin.

Nexus Recommended Beginning Lot Sizes

Cent / ProCent Account 0.10 lot per $1,000

Recommended starting reference: approximately 0.10 lot per $1,000 account size. Example: a $2,000-equivalent Cent / ProCent account would begin around 0.20 lot.

Non-Cent Account 0.01 lot per $50,000

Recommended starting reference: approximately 0.01 lot per $50,000 account size for a non-cent account.

These Are Beginning Reference Levels — Not Guaranteed Safe Levels Account type, leverage, margin requirements, contract size, broker specifications and your personal risk tolerance can all affect the appropriate lot size. If unsure, begin smaller rather than larger and validate the behaviour on demo first.
Existing Nexus Screenshot — Risk / Lot Input Example Example MetaTrader EA lot size or risk input
Example of a Nexus lot-size input. Set an appropriate starting size for your account and risk tolerance.
Existing Nexus Screenshot — Apply Settings Click OK to apply Expert Advisor settings
Once the correct preset, lot size and permissions are confirmed, click OK to apply the EA settings.
Step 11

Turn Automated Trading On

Attaching the EA is not enough if MetaTrader is preventing automated execution.

11A — MT4

Enable AutoTrading

If MT4 shows the EA attached but AutoTrading is off, Nexus cannot execute trades.

Existing Nexus Screenshot — EA Inactive MT4 EA inactive example
MT4 example: an inactive EA indicates trading automation is not currently available.
Existing Nexus Screenshot — AutoTrading Off MT4 AutoTrading disabled
MT4 AutoTrading switched off.
Existing Nexus Screenshot — AutoTrading On MT4 AutoTrading enabled
Enable AutoTrading before expecting the EA to execute orders.
Existing Nexus Screenshot — Nexus Active Nexus EA active in MT4
MT4 example of Nexus active on the chart.
11B — MT5

Enable Algo Trading and Confirm the Running EA

  1. Enable Algo Trading on the main toolbar.
  2. Confirm global Expert Advisor trading is permitted.
  3. Confirm the individual Nexus EA is permitted to trade.
  4. Check the Navigator/list of running EAs to ensure Nexus is attached to the intended chart.
  5. Open Toolbox → Experts and Journal and confirm there are no permission or licence errors.
Do Not Look for the MT4 Smiley Face in MT5 MT5 uses different EA status indicators. The reliable checks are the Algo Trading control, EA status and Experts/Journal logs.
MT5 Visual Reference — Running Expert Advisors

MetaQuotes documents how MT5 displays and manages Expert Advisors running on connected charts.

Open Official MT5 Running-EA Guide ↗
Step 12

Perform a Final Installation Check

Confirm every item below before leaving the EA unattended.

Correct licensed account is logged in
Broker connection is active
Correct EURUSD / GBPUSD symbol is open
GBPUSD = M5 / EURUSD = M15
Correct Nexus EA is attached
Correct current preset is loaded
Intended risk profile is selected
Lot size has been reviewed
AutoTrading / Algo Trading is enabled
No licence errors in logs
No invalid-volume or execution errors
VPS will remain online
MetaTrader restart method is understood
You are starting on demo
No Trade Yet Does Not Mean the Installation Failed Nexus waits for its programmed entry conditions. If the EA is active, connected and error-free, it may legitimately remain idle for a period of time.
Step 13 — Required

Always Validate Nexus on Demo First

Demo validation is a required part of the Nexus self-service setup process.

Required — Do Not Move Straight to Live Trading After installation, run Nexus on a demo account for at least 4–6 weeks or longer before considering live trading. The objective is to understand the EA's behaviour, verify your installation and identify broker, VPS, lot-size or configuration problems before real capital is exposed.

During the 4–6 Week Demo Validation Period

  • Leave the EA running continuously through normal market conditions.
  • Compare the EA's behaviour with your expectations and with the Nexus setup documentation.
  • Observe how often trades occur and how trades are managed.
  • Review drawdown and make sure the selected lot size remains within your own risk tolerance.
  • Check the Experts and Journal tabs regularly for warnings, licence messages, execution problems or recurring errors.
  • Confirm the platform remains connected and the EA remains attached after VPS reconnects, Windows updates or platform restarts.
  • Do not increase lot size simply because a small number of demo trades were profitable.
Platform remains online
EA remains attached after reconnecting
Preset remains loaded
Orders execute when conditions occur
Spreads are reasonable for your broker
No recurring Journal / Experts errors
Trade management behaves as expected
Equity protection behaves as documented
GBPUSD remains on M5
EURUSD remains on M15
Lot size remains appropriate
VPS uptime is stable
Demo First — Minimum 4–6 Weeks A demo account is not identical to live execution, but it is the correct environment to learn how Nexus behaves and identify installation, permission, preset, lot-size and VPS problems before using real capital.
Step 14

Move to Live Carefully

Only consider live trading after completing your demo validation period.

Recommended Live Starting Approach After at least 4–6 weeks of successful demo validation, move to live cautiously. Where available and appropriate, Nexus recommends beginning with a ProCent / Cent account and a small position size rather than immediately using a large standard account or high lot size.
  • Complete at least 4–6 weeks of demo validation first.
  • Start live with a small position size.
  • Where appropriate, start on a ProCent / Cent account so live behaviour can be observed with lower monetary exposure.
  • Monitor the account daily, particularly during the first few weeks.
  • Adjust lot size only when required to keep risk low and consistent with your own account settings.
  • Do not increase lot size rapidly following a profitable period.
  • Check the VPS each morning or use a VPS uptime-monitoring service.
  • Confirm MT4 / MT5 automatically restarts after Windows updates or VPS reboots.
  • Consider placing the MetaTrader shortcut in the Windows Startup folder using Win + R → shell:startup.
  • Even when Startup is configured, manually verify MetaTrader, broker connectivity, chart settings and EA status after any restart.
Daily Check

Confirm the VPS is online, MT4/MT5 is connected, AutoTrading/Algo Trading is enabled, Nexus remains attached and there are no new errors in Experts or Journal.

Risk Check

Review account equity, drawdown, open exposure and current lot size. Keep the position size low until you are fully comfortable with the EA's live behaviour.

Going Live Does Not Mean Increasing Risk The goal when moving from demo to live is to confirm that the EA behaves correctly under real broker execution. It is not an invitation to immediately use larger lot sizes.
Self-Service Quick Reference

Nexus EA Essential Operating Settings

Use this section as a quick reference after the installation is complete.

GBPUSD Chart

GBPUSD Nexus EA: 5 Minute Chart — M5.

EURUSD Chart

EURUSD Nexus EA: 15 Minute Chart — M15.

Demo Validation

Required: run Nexus on demo for at least 4–6 weeks or longer before live trading.

Demo Monitoring

Compare behaviour to expectations and regularly review Experts and Journal for errors.

Cent / ProCent Starting Lot

Beginning reference: 0.10 lot per $1,000 account size. Example: $2,000 = approximately 0.20 lot.

Non-Cent Starting Lot

Beginning reference: 0.01 lot per $50,000 account size.

VPS Monitoring

Check the VPS each morning or use an uptime monitor. Verify MetaTrader restarts after Windows updates.

Live Trading

Start carefully, preferably with lower exposure, keep lot size small and monitor the account daily.

Important The lot-size examples above are intended as conservative beginning reference points for learning and validation. They do not guarantee a particular drawdown, loss limit or trading outcome. Your account type, margin, leverage, broker contract specifications and personal risk tolerance must always be considered.
Troubleshooting

Self-Service Troubleshooting

Work through the matching issue before contacting support.

EA does not appear in Navigator
MT4: verify the file is in MQL4 → Experts and is the correct MT4 build. MT5: verify it is in MQL5 → Experts and is the correct MT5 build. Refresh Navigator and restart MetaTrader if necessary.
MT5 Nexus file is in Experts but still does not appear
Confirm you opened the data folder from inside the exact MT5 terminal you are using. Multiple MetaTrader installations can have different data folders. Also confirm the file is the supplied MT5 compiled build rather than an MT4 .ex4 file.
EA is attached but no trades are opening
This may be normal. Confirm there are no licence or permissions errors, that the correct pair, timeframe and preset are loaded, and that AutoTrading / Algo Trading is enabled. GBPUSD should be on M5 and EURUSD should be on M15. If there are no errors, the strategy may simply be waiting for valid entry conditions.
I see a licence error
Confirm MetaTrader is logged into the exact account authorised for your Nexus licence. If correct, contact Nexus with the broker, platform and account number. Never send your password.
MT4 says AutoTrading is off
Enable the AutoTrading toolbar control and check the EA's Common-tab permission to allow trading.
MT5 says automated trading is disabled
Check: (1) the main Algo Trading control, (2) Tools → Options → Expert Advisors, and (3) the Nexus EA's own automated-trading permission. Then inspect Toolbox → Experts and Journal for the exact message.
Invalid volume / lot-size error
Your requested volume may be below the broker minimum, above the maximum or not aligned to the broker's volume step. Review the symbol specification and reduce the lot size if necessary. Remember that the Nexus beginning reference is approximately 0.10 lot per $1,000 for Cent / ProCent accounts and 0.01 lot per $50,000 for non-cent accounts, but broker specifications and your own risk limits always take priority.
Wrong symbol or no EURUSD / GBPUSD in Market Watch
Use Market Watch to show all required symbols. Some brokers use suffixes such as EURUSD.a or EURUSDm. Do not rename a chart; open the broker's actual tradable symbol.
I accidentally used the wrong timeframe
Remove or stop the EA, select the correct timeframe and confirm the EA and preset are loaded correctly. GBPUSD uses M5. EURUSD uses M15.
MT4 / MT5 loses connection
Confirm internet/VPS connectivity, correct broker server and broker service status. If the platform reconnects, verify the EA is still active and automation remains enabled.
MetaTrader did not restart after a VPS reboot
Reopen MetaTrader manually and verify the correct account, chart, EA and automation status. Optionally configure a startup shortcut using Win + R → shell:startup. Always verify the platform after Windows updates or a VPS reboot.
Where do I find useful error messages?
MT4: Terminal → Experts / Journal. MT5: Toolbox → Experts / Journal. Copy the exact error text or code when contacting Nexus support.
Can I manually edit the Nexus inputs?
Use the supplied presets unless you understand exactly what the parameter changes. Manual changes can materially alter entries, exits and risk.
How long should I test on demo?
Nexus requires clients to validate the installation on demo first. Run the EA for at least 4–6 weeks or longer. During this period, compare behaviour to your expectations, monitor drawdown and regularly review the Experts and Journal tabs for errors.

Still Need Help?

If you have worked through the guide and your Nexus licence is active, contact support with your broker name, MT4 or MT5, trading account number, the step where the problem occurs, and the exact Experts/Journal error message. Never send your password.

Contact Nexus Support → Preferred Brokers & VPS →
Risk Warning: Forex and CFD trading involves significant risk and can result in loss of capital. This installation guide explains software setup and does not guarantee that the EA will trade profitably. Past performance, live results and backtests do not guarantee future performance. Always validate Nexus on demo for at least 4–6 weeks before considering live trading. Keep initial position sizes low, monitor your own risk and only trade capital you can afford to lose.