.CER File Extension

File Type:
Internet Security Certificate

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

What is a CER file?

Cer file extension has Internet Security Certificate file type, which is associated with the "web files" category.

Security files created by a third party Certificate Authority in order to verify the authenticity of a website have this extension. A website administrator has to install a CER file on a web server. This way the validity of a website on a concrete server can be established.

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

cer file icon
File Type:
Internet Security Certificate
Web Files

How to open CER file?

Double click the cer 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 .cer 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 cer 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 cer 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 CER 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 cer file as well. Download Universal File Viewer for your OS.

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Download for Mac
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