Why Developers Prefer EX4 Files

Most developers distribute EX4 files only because they:

• Protect trading strategies
• Prevent copying or resale
• Secure intellectual property
• Reduce the risk of unauthorized modification

Sharing an MQ4 file gives full access to the strategy logic, which is why it is usually kept private.

Why Some Traders Request MQ4 Files

Traders may want MQ4 files to:

• Customize trading rules
• Adjust risk parameters
• Learn MQL4 programming
• Audit strategy logic (with permission)

However, developers typically only provide MQ4 files under:

• Private agreements
• Paid customization services
• Employment or partnership contracts

How EX4 and MQ4 Files Work Together

The typical workflow looks like this:

1. Developer writes the strategy in an MQ4 file
2. MQ4 file is compiled in MetaEditor
3. Compilation produces an EX4 file
4. EX4 file is placed in the MT4 Experts or Indicators folder
5. MT4 executes the EX4 file during trading

MT4 cannot run MQ4 files directly — only EX4 files.

Security and Legal Considerations

• MQ4 files are protected under copyright law
• EX4 files are intentionally designed to prevent reverse-engineering
• Unauthorized modification or redistribution violates MetaQuotes’ terms
• Respecting file ownership is critical for legal and ethical trading

Always ensure you have the right to use, modify, or request source code.

EX4 vs MQ4: Which One Do You Need?

You Need an MQ4 File If:

• You are developing or learning MQL4
• You need custom changes
• You own the strategy logic

You Need an EX4 File If:

• You just want to trade
• You bought or downloaded an EA
• You don’t need to edit the strategy

Most traders only ever need EX4 files.

EX4 and MQ4 in Modern Trading

Although MT5 is now the focus of MetaQuotes, MT4 remains widely used. Understanding EX4 and MQ4 files helps traders:

• Choose reliable EAs
• Avoid scams
• Communicate better with developers
• Protect their investments

Final Thoughts

The difference between EX4 and MQ4 files comes down to execution versus creation.

• MQ4 is the editable source code used to build trading strategies
• EX4 is the compiled, protected file used to run those strategies in MT4

Knowing this distinction empowers you to make smarter decisions as a trader or developer in the MetaTrader ecosystem.