How to Read the MT4 Experts and Journal Logs

Before you start

• MetaTrader 4 with an Expert Advisor attached to a chart.

What you'll learn

• Tell the Experts log and the Journal apart.
• Find error lines and their codes.
• Open the log files on disk and share the relevant part.

Steps

1. 1

   Step 1: Open the Terminal window

   Press Ctrl+T (or View → Terminal). The tabs along its bottom edge include Experts and Journal.

   Mark as done: Open the Terminal window
2. 2

   Step 2: Read the Experts tab

   Experts shows messages from EAs and indicators: when they load or are removed, anything their code prints, and errors such as a rejected order. Each line has a time, the program's name and the symbol and timeframe it runs on.

   Mark as done: Read the Experts tab
3. 3

   Step 3: Read the Journal tab

   Journal shows platform events: logging in, connection lost or restored, orders sent and the broker's response. If an EA "did nothing", the Journal shows whether an order ever reached the broker.

   Mark as done: Read the Journal tab
4. 4

   Step 4: Look for error codes

   Errors are usually reported with a number. Common ones in MT4:

   • 4109 — trading not allowed (AutoTrading or Allow live trading is off).
   • 130 — invalid stops (stop-loss/take-profit too close or on the wrong side).
   • 131 — invalid trade volume.
   • 134 — not enough money (free margin).

   Mark as done: Look for error codes
5. 5

   Step 5: Open the log files on disk

   Right-click inside the Experts or Journal tab and choose Open. This opens the folder with the day's log files, named by date (for example 20261014.log) — the Journal's in the data folder's logs folder and the Experts log in MQL4\Logs.

   Mark as done: Open the log files on disk
6. 6

   Step 6: Share the right lines

   When asking a developer for help, copy the lines from a few minutes before and after the problem, plus your MT4 build number (Help → About) and your broker. On FXBotHub, send them with Contact seller on the product page.

   Log lines can include your account number. Remove anything you don't want to share before sending them.

   Mark as done: Share the right lines

Troubleshooting

The Experts tab is empty

No EA has printed anything yet, or none is attached. Re-attach the EA and watch for its load message.

Too many lines to read

Right-click the tab and use the option to clear the view (the file on disk is kept), then reproduce the problem so only new lines appear.

Official documentation

• MQL4 documentation (opens in a new tab)