How to install a custom indicator in MetaTrader 5
Desktop MT5 can load compiled or source indicators. The standard mobile apps cannot install desktop MQL5 files, so the correct workflow depends on the device.
Know what you downloaded.
An .mq5 file is readable MQL5 source code; an .ex5 file is compiled for MetaTrader 5. MT4 files such as .mq4 and .ex4 are not interchangeable with MT5 files.
Prefer source you can inspect, a stated version, a checksum and documentation that explains inputs, repaint behaviour and permissions. Never treat a free indicator as safe merely because it compiles.
Place the file in the platform data folder.
In MT5, choose File, then Open Data Folder. Open MQL5 and Indicators, copy the file into that folder, return to MT5 and refresh the Navigator or restart the platform.
For .mq5 source, open MetaEditor, compile the file and read every warning or error. The compiled .ex5 should appear in the corresponding Indicators folder.
Test the output before trusting the display.
Drag the indicator from Navigator onto a demo chart, record the inputs and confirm that the expected buffers or objects appear. Change timeframe and reload the platform to check persistence.
Use historical bar replay or a documented observation test to see whether earlier signals move, disappear or use future information. A 'non-repainting' label is a claim to test, not accept.
MT5 mobile is not desktop MT5.
The standard MetaTrader 5 apps for iPhone and Android provide a fixed collection of built-in indicators. They do not load ordinary desktop .mq5 or .ex5 custom indicators.
A desktop or hosted terminal can run the indicator, but merely viewing the same account on mobile does not reproduce custom chart output. Avoid websites that imply a normal mobile install where the platform does not support one.
When the indicator does not appear
Confirm that you opened the data folder for the terminal you are actually using, the file is in MQL5/Indicators rather than Experts, and the code compiled for MT5 without errors. Refresh Navigator and inspect the Experts and Journal tabs.
If output is blank, check symbol/timeframe assumptions, minimum bars, input ranges and whether the tool depends on data that has not downloaded. Remove the indicator if it requests unexplained DLL or network permissions.
- Correct MT5 data folder
- Correct file type and subfolder
- Successful compile
- Enough price history
- No unexplained external permissions
- Demo verification before broader use