.INI Files: What They Are, What They Are For, and How to Use Them

Surely on some occasion you have come across a .INI file hidden in the system or among the files of some program that you just installed. Although at first glance they may seem irrelevant or even suspicious, these small files play a crucial role in configuring applications and OS.

.INI files have long been a key piece in defining the behavior of programs, whether in Windows or other environmentsAlthough their use has declined in favor of technologies like the Windows Registry, JSON, or XML, they are still present, especially in older software and applications where simplicity and readability are a priority.

What is an .INI file?

A file with the .INI extension is a plain text document used primarily to store settings and preferences. of programs. It is a legacy format that became popular in Microsoft operating systems, especially in versions such as Windows 3.x and Windows 95, where it became the standard way to store system and application customization settings.

This type of file is structured in a simple but efficient way: is divided into sections marked with brackets (for example, ), and each section contains key-value pairs that define different parameters (for example, Path=C:\Files). You can also add comments using the ; or # symbol at the beginning of a line.

Due to their accessible format, they are readable by anyone and can be opened with text editors such as Notepad or Notepad++.They do not require complex tools or special privileges to be modified (although it is advisable to do so with caution).

Basic structure of .INI files

The hierarchical structure of .INI files is very easy to interpret., which has contributed to its widespread use in past decades. It generally includes:

• Sections: delimited by brackets, they group related parameters.
• Keys: are the names of the settings we want to establish.
• Values: associated with the keys, they define their behavior.
• Comments: add descriptions without affecting functionality.

For example:

Servidor=localhost
Puerto=3306
Usuario=admin
Clave=secreta


Ruta=/var/logs/app.log
Nivel=INFO

Applications read these files when they start, thus applying the settings defined by the user or developer.This approach allows you to modify behavior without touching the source code.

What are .INI files used for?

.INI files are used to define parameters related to the behavior, appearance, or functionality of a program.With them, users can specify file paths, custom preferences, connection types, software language, and many other options.

Although in modern versions of Windows its use has decreased in favor of the Registry, systems such as Tekla Structures still use them widely to establish environment-specific configurations in different functions such as steel, concrete or engineering.

Among the most common uses are:

• Program settings: indicate language, subject, directories or access levels.
• Connections to databases: save IP, port and credentials.
• User Preferences: window size, position, recent history.
• System Initialization Settings: as it was in Windows 3.1 or 95.

This type of file can also be used by malware to modify settings, but it itself cannot execute malicious code since it is just plain text.

Real examples of .INI files

A basic example of a .INI file might look like this:

; Configuración general de la aplicación

Nombre=MiPrograma
ModoOscuro=Sí
Idioma=es-ES


Servidor=127.0.0.1
Puerto=5432
Usuario=admin
Contraseña=passwordsegura


LogNivel=DEBUG
LogRuta=C:\logs\miapp.log

As you can see, each section groups different types of configurations. that are part of the software, from the visual appearance to technical parameters such as the database.

Advantages and disadvantages of .INI files

The .INI format stands out for its simplicity and ease of use., but it is not without limitations, especially in more modern environments where more complex structures need to be handled.

Advantages

• Easy to read and edit: : no special tools required.
• Lightweight: Its small size makes it easy to use in lightweight software.
• Multiplatform: can be used on Windows, Linux or macOS.
• Annotations through comments: ideal for internal documentation.

Disadvantages

• Does not support complex data structures: such as lists or deep hierarchies.
• Lack of strict standardization: : each software can interpret it differently.
• Difficulty climbing: When they grow, they become prone to errors and difficult maintenance.
• Security risk: can contain plain text passwords if not properly protected.

How to create and edit an .INI file?

Creating an .INI file is as simple as opening Notepad and saving the file with the .ini extension.However, there are certain good practices that should be kept in mind:

1. Use a plain text editor like Notepad++, VS Code or the classic Notepad.
2. Do not use special characters in passwords like ; or =.
3. Always organize settings into separate sections.
4. Save the file with ANSI or UTF-8 encoding to avoid reading errors.

To open one, just right-click and select “Open with…” → NotepadFrom there you can inspect or modify it, although it's recommended to make a copy before editing anything.

Related article:

How to Download and Use File Manager to Organize and Manage Your Data

Can I delete an .INI file from the system?

In theory, you can delete an .INI file, but you should know what it does before doing so.If it belongs to an app, deleting it may cause it to revert to its default settings or even stop working properly.

In the case of important system files such as win.ini or system.ini on older Windows systems, its removal may cause instability or serious failures.

But if it is a .INI file from an uninstalled application or one you no longer use, you can delete it without any problemYou can even automate this cleanup using software like CCleaner or BleachBit.

You can also use commands from the Windows console (CMD) to delete them all with:

del *.ini /s

This command will delete all .INI files within a directory and its subfolders, but again, caution is advised.

Can .INI files be viruses?

No, .INI files alone cannot execute code or infect your computer.. They are simply text documents that contain configuration parameters.

However, malware can use them to modify a legitimate application's configuration and make it behave maliciously. For example, instructing it to load a malicious DLL or execute a file at system startup.

It is always advisable to scan any suspicious .INI file with antivirus software., especially if it comes from untrustworthy sources. But in most cases, they're completely harmless.

Common situations with .INI files in Windows

Many times you can see files like desktop.ini in system or desktop folders. These are used to save display settings for that specific folder, such as the icon or local name.

They are not dangerous, and there is no need to remove them.In fact, if you do, Windows will automatically regenerate them as soon as you make any changes to the view of that folder.

To hide these files, simply disable the “Show hidden files” option in Windows File Explorer.

Some more advanced users may edit desktop.ini to customize icons or behaviors for specific folders, although this is not common.

.INI files are still present in many systems and programs, despite having been largely replaced by the Windows Registry or more modern formats like JSON and YAML, its use persists due to its simplicity, portability, and broad compatibility.

Knowing how to interpret and modify them will give you greater control over key settings and make it easier to troubleshoot problems that would otherwise be more difficult. Always back up your data and be careful.

Isaac

Passionate writer about the world of bytes and technology in general. I love sharing my knowledge through writing, and that's what I'll do on this blog, show you all the most interesting things about gadgets, software, hardware, tech trends, and more. My goal is to help you navigate the digital world in a simple and entertaining way.