If you are installing a third-party indicator, the following steps should be followed:
Click on "File - Open Data Folder" in MT4:
In the opened window we enter the MQL4 - Indicators folder:
and place the indicator you use there:
In the "Navigator" window of MT4, you should press the right button in the "Indicator" group and then press the "Update" button:
Find the indicator in the list and double-click the left mouse button or "drag" the indicator to the chart:
