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- From theory to practice
- Looking for patterns
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There is one article which every seller on the market should read: it is about validation of the Market products -
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The checks a trading robot must pass before publication in the Market
Before any product is published in the Market, it must undergo compulsory preliminary checks, as a small error in the expert or indicator logic can cause losses on the trading account. That is why we have developed a series of basic checks to ensure the required quality level of the Market products.
- How to quickly catch and fix errors in trading robots
- Insufficient funds to perform trade operation
- Invalid volumes in trade operations
- Limiting Number of Pending Orders
- Limiting Number of Lots by a Specific Symbol
- Setting the TakeProfit and StopLoss levels within the SYMBOL_TRADE_STOPS_LEVEL minimum level
- Attempt to modify order or position within the SYMBOL_TRADE_FREEZE_LEVEL freeze level
- Errors that occur when working with symbols which have insufficient quote history
- Array out of Range
- Zero Divide
- Sending a request to modify the levels without actually changing them
- Attempt to import compiled files (even EX4/EX5) and DLL
- Calling custom indicators with iCustom()
- Passing an invalid parameter to the function (runtime error)
- Access violation
- Consumption of the CPU resources and memory
- Articles for reading
If any errors are identified by the Market moderators in the process of checking your product, you will have to fix all of them. This article considers the most frequent errors made by developers in their trading robots and technical indicators. We also recommend reading the following articles:
![MQL5 - Language of trade strategies built-in the MetaTrader 5 client terminal](https://c.mql5.com/i/registerlandings/logo-2.png)
- Free trading apps
- Over 8,000 signals for copying
- Economic news for exploring financial markets
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