.DEF File Extension

Developer:
IObit
File Type:
IOBit Malware Fighter Definitions File
Popularity:

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

What is a DEF file?

Def file extension has IOBit Malware Fighter Definitions file type, developed by IObit, which is associated with the "data files" category.

Associated with IObit Malware Fighter, the file defines viruses. These definitions may be used to detect and remove malicious software from user’s PC.

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

def file icon
Developer:
IObit
File Type:
IOBit Malware Fighter Definitions File
Category:
Data Files
Format:
Binary

How to open DEF file?

Double click the def 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 .def 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 def 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".
4.455.664 downloads

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 def 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 DEF files

  • Windows Windows
    • IObit Malware Fighter IObit Malware Fighter

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 def file as well. Download Universal File Viewer for your OS.

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