ER_ File Extension

ER_ file icon
Microsoft Winhelp Compressed
  • Developer
    Microsoft Corporation
  • Popularity
    3.2 (5 votes)

What is ER_ file?

ER_ filename suffix is mostly used for Microsoft Winhelp Compressed files. Microsoft Winhelp Compressed format was developed by Microsoft Corporation. ER_ files are supported by software applications available for devices running Windows. ER_ file format, along with 3591 other file formats, belongs to the Various Files category. The most popular software that supports ER_ files is Microsoft Windows Help. On the official website of Microsoft Corporation developer not only will you find detailed information about theMicrosoft Windows Help software, but also about ER_ and other supported file formats.

Programs which support ER_ file extension

Programs that can handle ER_ files are as follows. Files with ER_ suffix can be copied to any mobile device or system platform, but it may not be possible to open them properly on target system.

Programs that support ER_ file

How to open file with ER_ extension?

There can be multiple causes why you have problems with opening ER_ files on given system. On the bright side, the most encountered issues pertaining to Microsoft Winhelp Compressed files aren’t complex. In most cases they can be addressed swiftly and effectively without assistance from a specialist. We have prepared a listing of which will help you resolve your problems with ER_ files.

Step 1. Download and install Microsoft Windows Help

Problems with opening and working with ER_ files are most probably having to do with no proper software compatible with ER_ files being present on your machine. The solution is straightforward, just download and install Microsoft Windows Help. On the top of the page a list that contains all programs grouped based on operating systems supported can be found. The safest method of downloading Microsoft Windows Help installed is by going to developer’s website (Microsoft Corporation) and downloading the software using provided links.

Step 2. Check the version of Microsoft Windows Help and update if needed

You still cannot access ER_ files although Microsoft Windows Help is installed on your system? Make sure that the software is up to date. It may also happen that software creators by updating their applications add compatibility with other, newer file formats. If you have an older version of Microsoft Windows Help installed, it may not support ER_ format. 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 Windows Help.

Step 3. Assign Microsoft Windows Help to ER_ files

After installing Microsoft Windows Help (the most recent version) make sure that it is set as the default application to open ER_ 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 ER_ file and choose Open with option
  • Select Choose another app → More apps
  • The last step is to select Look for another app on this PC option supply the directory path to the folder where Microsoft Windows Help is installed. Now all that is left is to confirm your choice by selecting Always use this app to open ER_ files and clicking OK.

Selecting the first-choice application in Mac OS

  • By clicking right mouse button on the selected ER_ file open the file menu and choose Information
  • Find the Open with option – click the title if its hidden
  • Select Microsoft Windows Help and click Change for all...
  • If you followed the previous steps a message should appear: This change will be applied to all files with ER_ extension. Next, click the Continue button to finalize the process.

Step 4. Check the ER_ for errors

If you followed the instructions form the previous steps yet the issue is still not solved, you should verify the ER_ file in question. Problems with opening the file may arise due to various reasons.

1. The ER_ may be infected with malware – make sure to scan it with an antivirus tool.

If the ER_ is indeed infected, it is possible that the malware is blocking it from opening. Scan the ER_ file as well as your computer for malware or viruses. ER_ file is infected with malware? Follow the steps suggested by your antivirus software.

2. Verify that the ER_ file’s structure is intact

If you obtained the problematic ER_ file from a third party, ask them to supply you with another copy. The file might have been copied erroneously and the data lost integrity, which precludes from accessing the file. When downloading the file with ER_ extension from the internet an error may occurred resulting in incomplete file. Try downloading the file again.

3. Verify whether your account has administrative rights

Sometimes in order to access files user need to have administrative privileges. Log in using an administrative account and see If this solves the problem.

4. Verify that your device fulfills the requirements to be able to open Microsoft Windows Help

The operating systems may note enough free resources to run the application that support ER_ files. Close all running programs and try opening the ER_ file.

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 Microsoft Winhelp Compressed 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 ER_ files.

Do you want to help?

If you have additional information about the ER_ 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 ER_ file.

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