What is mql file? How to open mql files?
The mql file extension is associated with the MetaTrader. It is a trading software to provide brokerage services. The MetaTrader uses indicator files to view situations on selected stock services.
The default software associated to open mql file:

MetaTrader 
Company or developer:
MetaQuotes Software Corp.
MetaTrader is designed to provide brokerage services to customers in Forex, CFD and Futures, as well as equity markets.
Help how to open:
This file type is not meant to be opened directly, there is no software that could open and work with it directly, or there is no information available in public sources about opening this file type. This is usually the case of some internal data files, caches, temporary files etc.
How to convert:
As far as we know, this .mql file type can't be converted to any other file format. This is usually the case of system, configuration, temporary, or data files containing data exclusive to only one software and used for its own purposes. Also some proprietary or closed file formats cannot be converted to more common file types in order to protect the intellectual property of the developer, which is for example the case of some DRM-protected multimedia files.
File identification strings:
HEX code: 2F 2A 5B 5B 0D 0A
ASCII code: /*[[
List of software applications associated to the .mql file extension
Recommended software programs are sorted by OS platform (Windows, macOS, Linux, iOS, Android etc.)
and possible program actions that can be done with the file: like open mql file, edit mql file, convert mql file, view mql file, play mql file etc. (if exist software for corresponding action in File-Extensions.org's database).
Hint:
Click on the tab below to simply browse between the application actions, to quickly get a list of recommended software, which is able to perform the specified software action, such as opening, editing or converting mql files.
Software that open mql file - MetaTrader indicator file
Programs supporting the exension mql on the main platforms Windows, Mac, Linux or mobile. Click on the link to get more information about MetaTrader for open mql file action.
mql file editor and apps that can edit mql file - MetaTrader indicator file
Programs supporting the exension mql on the main platforms Windows, Mac, Linux or mobile. Click on the link to get more information about MetaTrader for edit mql file action.
Programs that can create mql file - MetaTrader indicator file
Programs supporting the exension mql on the main platforms Windows, Mac, Linux or mobile. Click on the link to get more information about MetaTrader for create mql file action.
Unspecified and all other actions for computer programs working with mql file - MetaTrader indicator file
Click on the software link for more information about MetaTrader. MetaTrader uses mql file type for its internal purposes and/or also by different way than common edit or open file actions (eg. to install/execute/support an application itself, to store application or user data, configure program etc.).
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