- November 24, 2025
Reading the Log
Overview When you develop programs in MQL5, the log is your primary source of truth about what is actually happening inside the terminal. MetaTrader 5 records messages from your Expert Advisors, indicators, and scripts, along with system events and errors. These messages are shown in different tabs such as Experts, Journal, and, when testing, the Strategy Tester output. Learning how to read these logs will dramatically improve your ability to debug and refine your trading algorithms. What You Will Be Able to Do Code Example Execution Steps Key Point Effective debugging in MQL5 starts with the log. By combining meaningful Print() messages with careful reading of the Experts and Journal tabs, you can understand the exact sequence of events, detect errors early, and verify that your trading logic behaves as expected. Next Section → Next: Summary and Next Steps