DER File Extension

DER file icon
DER Certificate Format

What is DER file?

DER is a file extension commonly associated with DER Certificate Format files. Files with DER extension may be used by programs distributed for Linux, Mac OS, Windows platform. DER file belongs to the Web Files category just like 303 other filename extensions listed in our database. Microsoft Internet Explorer supports DER files and is the most frequently used program to handle such files, yet 5 other tools may also be used. Software named Microsoft Internet Explorer was created by Microsoft Corporation. In order to find more detailed information on the software and DER files, check the developer’s official website.

Programs which support DER file extension

The following list contains programs grouped by 3 operating systems that support DER files. DER files can be encountered on all system platforms, including mobile, yet there is no guarantee each will properly support such files.

Programs that support DER file

How to open file with DER extension?

Being unable to open files with DER extension can be have various origins. What is important, all common issues related to files with DER extension can be resolved by the users themselves. The process is quick and doesn’t involve an IT expert. The following is a list of guidelines that will help you identify and solve file-related problems.

Step 1. Get the Microsoft Internet Explorer

The main and most frequent cause precluding users form opening DER files is that no program that can handle DER files is installed on user’s system. The most obvious solution is to download and install Microsoft Internet Explorer or one to the listed programs: Opera, Mozilla Firefox, Safari. Above you will find a complete listing of programs that support DER files, classified according to system platforms for which they are available. If you want to download Microsoft Internet Explorer installer in the most secured manner, we suggest you visit Microsoft Corporation website and download from their official repositories.

Step 2. Check the version of Microsoft Internet Explorer and update if needed

If the problems with opening DER files still occur even after installing Microsoft Internet Explorer, it is possible that you have an outdated version of the software. Check the developer’s website whether a newer version of Microsoft Internet Explorer is available. Software developers may implement support for more modern file formats in updated versions of their products. The reason that Microsoft Internet Explorer cannot handle files with DER may be that the software is outdated. All of the file formats that were handled just fine by the previous versions of given program should be also possible to open using Microsoft Internet Explorer.

Step 3. Associate DER Certificate Format files with Microsoft Internet Explorer

After installing Microsoft Internet Explorer (the most recent version) make sure that it is set as the default application to open DER files. The process of associating file formats with default application may differ in details depending on platform, but the basic procedure is very similar.

Selecting the first-choice application in Windows

  • Right-click the DER file and choose Open with option
  • Next, select the Choose another app option and then using More apps open the list of available applications
  • The last step is to select Look for another app on this PC option supply the directory path to the folder where Microsoft Internet Explorer is installed. Now all that is left is to confirm your choice by selecting Always use this app to open DER files and clicking OK.

Selecting the first-choice application in Mac OS

  • By clicking right mouse button on the selected DER file open the file menu and choose Information
  • Proceed to the Open with section. If its closed, click the title to access available options
  • From the list choose the appropriate program and confirm by clicking Change for all....
  • Finally, a This change will be applied to all files with DER extension message should pop-up. Click Continue button in order to confirm your choice.

Step 4. Ensure that the DER file is complete and free of errors

You closely followed the steps listed in points 1-3, but the problem is still present? You should check whether the file is a proper DER file. Problems with opening the file may arise due to various reasons.

1. Verify that the DER in question is not infected with a computer virus

Should it happed that the DER is infected with a virus, this may be that cause that prevents you from accessing it. Scan the DER file as well as your computer for malware or viruses. DER file is infected with malware? Follow the steps suggested by your antivirus software.

2. Ensure the file with DER extension is complete and error-free

Did you receive the DER file in question from a different person? Ask him/her to send it one more time. It is possible that the file has not been properly copied to a data storage and is incomplete and therefore cannot be opened. If the DER file has been downloaded from the internet only partially, try to redownload it.

3. Check if the user that you are logged as has administrative privileges.

Sometimes in order to access files user need to have administrative privileges. Log out of your current account and log in to an account with sufficient access privileges. Then open the DER Certificate Format file.

4. Check whether your system can handle Microsoft Internet Explorer

If the systems has insufficient resources to open DER files, try closing all currently running applications and try again.

5. Check if you have the latest updates to the operating system and drivers

Latest versions of programs and drivers may help you solve problems with DER Certificate Format files and ensure security of your device and operating system. Outdated drivers or software may have caused the inability to use a peripheral device needed to handle DER files.

Do you want to help?

If you have additional information about the DER file, we will be grateful if you share it with our users. To do this, use the form here and send us your information on DER file.

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