ER1 File Extension

ER1 file icon
ERWin Entity Relationship Diagram
  • Developer
    Computer Associates
  • Category
  • Popularity
    3 (3 votes)

What is ER1 file?

ER1 is a file extension commonly associated with ERWin Entity Relationship Diagram files. ERWin Entity Relationship Diagram specification was created by Computer Associates. Files with ER1 extension may be used by programs distributed for Windows platform. ER1 file format, along with 1326 other file formats, belongs to the Data Files category. The most popular software that supports ER1 files is CA ERWin Data Modeler. Software named CA ERWin Data Modeler was created by CA Technologies. In order to find more detailed information on the software and ER1 files, check the developer’s official website.

Programs which support ER1 file extension

Below is a table that list programs that support ER1 files. ER1 files can be encountered on all system platforms, including mobile, yet there is no guarantee each will properly support such files.

Programs that support ER1 file

How to open file with ER1 extension?

Being unable to open files with ER1 extension can be have various origins. What is important, all common issues related to files with ER1 extension can be resolved by the users themselves. The process is quick and doesn’t involve an IT expert. The list below will guide you through the process of addressing the encountered problem.

Step 1. Install CA ERWin Data Modeler software

Install software to open ER1 file The main and most frequent cause precluding users form opening ER1 files is that no program that can handle ER1 files is installed on user’s system. To address this issue, go to the CA ERWin Data Modeler developer website, download the tool, and install it. It is that easy Above you will find a complete listing of programs that support ER1 files, classified according to system platforms for which they are available. If you want to download CA ERWin Data Modeler installer in the most secured manner, we suggest you visit CA Technologies website and download from their official repositories.

Step 2. Update CA ERWin Data Modeler to the latest version

Update software that support file extension ER1If you already have CA ERWin Data Modeler installed on your systems and ER1 files are still not opened properly, check if you have the latest version of the software. Software developers may implement support for more modern file formats in updated versions of their products. This can be one of the causes why ER1 files are not compatible with CA ERWin Data Modeler. The most recent version of CA ERWin Data Modeler is backward compatible and can handle file formats supported by older versions of the software.

Step 3. Set the default application to open ER1 files to CA ERWin Data Modeler

If the issue has not been solved in the previous step, you should associate ER1 files with latest version of CA ERWin Data Modeler you have installed on your device. The process of associating file formats with default application may differ in details depending on platform, but the basic procedure is very similar.

Associate software with ER1 file on Windows

Change the default application in Windows

  • Right-click the ER1 file and choose Open with option
  • Click Choose another app and then select More apps option
  • The last step is to select Look for another app on this PC option supply the directory path to the folder where CA ERWin Data Modeler is installed. Now all that is left is to confirm your choice by selecting Always use this app to open ER1 files and clicking OK.
Associate software with ER1 file on Mac

Change the default application in Mac OS

  • From the drop-down menu, accessed by clicking the file with ER1 extension, select Information
  • Open the Open with section by clicking its name
  • Select the appropriate software and save your settings by clicking Change all
  • Finally, a This change will be applied to all files with ER1 extension message should pop-up. Click Continue button in order to confirm your choice.

Step 4. Check the ER1 for 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 ER1 file. Being unable to access the file can be related to various issues.

Check ER1 file for viruses
1. The ER1 may be infected with malware – make sure to scan it with an antivirus tool.

If the ER1 is indeed infected, it is possible that the malware is blocking it from opening. Scan the ER1 file as well as your computer for malware or viruses. If the scanner detected that the ER1 file is unsafe, proceed as instructed by the antivirus program to neutralize the threat.

2. Ensure the file with ER1 extension is complete and error-free

Did you receive the ER1 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. It could happen the the download process of file with ER1 extension was interrupted and the file data is defective. Download the file again from the same source.

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

There is a possibility that the file in question can only be accessed by users with sufficient system privileges. Switch to an account that has required privileges and try opening the ERWin Entity Relationship Diagram file again.

4. Check whether your system can handle CA ERWin Data Modeler

If the system is under havy load, it may not be able to handle the program that you use to open files with ER1 extension. In this case close the other applications.

5. Verify that your operating system and drivers are up to date

Up-to-date system and drivers not only makes your computer more secure, but also may solve problems with ERWin Entity Relationship Diagram file. It is possible that one of the available system or driver updates may solve the problems with ER1 files affecting older versions of given software.

Do you want to help?

If you have additional information about the ER1 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 ER1 file.

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