.IDL File Extension

File Type:
Interface Definition Language File

Having trouble opening .idl extension? Don't panic! This page explains what idl files are as well as suggests programs you may use to open idl files. You can download these programs through this page.

What is a IDL file?

Idl file extension has Interface Definition Language file type, developed by Microsoft, which is associated with the "developer files" category.

These are source code files in the Microsoft Interface Definition Language. They are used to store type library and interface definitions. IDL files allow defining UIs between client and server apps. Can also be used for generating .TLB files (type libraries) for OLE automation.

To learn how you can open the given file, read the information below.

idl file icon
File Type:
Interface Definition Language File
Developer Files

How to open IDL file?

Double click the idl file to open it. The file will open automatically if file associations have been correctly installed and there is a proper program on your computer; if not, file associations may be corrupted and your OS either cannot find the proper program, or you might not have one for opening the file. First, we recommend downloading our utility to fix file association errors; then, you can download any program for opening the .idl extension from the ones suggested below. If you are certain there is nothing wrong with the file associations, you may proceed to method 2 right away; besides, if you can't make up your mind when choosing the right program, use Universal File Viewer from the last method.

Method 1: Fix file association errors

Follow these steps in order to automatically fix the idl extension associations' problem in no time:

  • Step 1: Click on "Download Solution" to download automatic tool provided by WikiExt.
  • Step 2: Click "Start Scan" to identify all potential issues.
  • Step 3: Review scan results and click "Fix Items".

File Size: 3.04 MB, Download time: < 1 min. on DSL/ADSL/Cable

This Tool is Compatible With: Windows XP, Vista, 7, 8/8.1, 10

Method 2: Download the appropriate software

The given list provides programs which may be used for opening or converting the idl file. Choose the proper program for your OS, and click it to start the download or proceed to the developer's website.

Programs that open IDL files

Method 3: Use universal file viewer

In addition to the list of programs above, we recommend using Universal File Viewer. This tool can open over 250 file extensions and, most likely, it will be able to open the idl file as well. Download Universal File Viewer for your OS.

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