Discussing the article: "Why My MQL5 EA Passed Validation and Still Failed Under Execution Delay"

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Check out the new article: Why My MQL5 EA Passed Validation and Still Failed Under Execution Delay.

An EA that passes CodeBase validation can still fail under execution delay and a freeze level. Using a tick scalper, the article reproduces four such failures in the Strategy Tester and shows each fix with its limits. An ablation under a fixed delay measures each change on its own. The burst-based stop distance removes most rejected modifications, while the weekend case behind the session buffer did not recur in those runs.

On 9 September 2026 I submitted a tick scalper to CodeBase five times in about half an hour. The first four submissions came back "Validation completed with errors", each with 21 errors, and the fifth passed. Only one report still shows its log. It says the test ran on EURUSD H1, while the EA is written for M1. That detail sent me looking for a timeframe bug that did not exist. The log lines themselves showed a forced close rejected because the position was too close to the market.

The real surprise came after the pass. When I rebuilt the test in my own Strategy Tester with execution delay, the published version still produced rejected stop modifications in every run. On a custom symbol, one position opened just before the weekend close started a chain of modifications aimed at the wrong position.

The main conclusion of this article is short. Passing validation did not show that the trading logic behaves correctly under execution delay. With a two-step entry, the question that matters is whether the EA keeps control of the position when a modify or a close fails or arrives late. In the builds tested here, it did not always keep that control.

Author: Ali Akbar