.DER File Extension

File Type:
DER Certificate File

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

What is a DER file?

Der file extension has DER Certificate file type, which is associated with the "web files" category.

These are digital certificates in the Distinguished Encoding Rules format. They store a binary form of the certificate and often used to save X.509 certificates. All popular Web browsers can work with digital certificates generated by trusted secure websites. 

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

der file icon
File Type:
DER Certificate File
Web Files

How to open DER file?

Double click the der 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 .der 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 der 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 der 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 DER 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 der file as well. Download Universal File Viewer for your OS.

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