INDX File Extension

INDX file icon
Microsoft Mail Index
  • Developer
    Microsoft Corporation
  • Category
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What is INDX file?

INDX is a file extension commonly associated with Microsoft Mail Index files. Microsoft Mail Index specification was created by Microsoft Corporation. Files with INDX extension may be used by programs distributed for Windows platform. Files with INDX extension are categorized as Database Files files. The Database Files subset comprises 348 various file formats. Microsoft Mail is by far the most used program for working with INDX files. Microsoft Mail software was developed by Microsoft Corporation, and on its official website you may find more information about INDX files or the Microsoft Mail software program.

Programs which support INDX file extension

Below is a table that list programs that support INDX files. Files with INDX extension, just like any other file formats, can be found on any operating system. The files in question may be transferred to other devices, be it mobile or stationary, yet not all systems may be capable of properly handling such files.

Programs that support INDX file

How to open file with INDX extension?

Being unable to open files with INDX extension can be have various origins. On the bright side, the most encountered issues pertaining to Microsoft Mail Index files aren’t complex. In most cases they can be addressed swiftly and effectively without assistance from a specialist. The list below will guide you through the process of addressing the encountered problem.

Step 1. Install Microsoft Mail software

The most common reason for such problems is the lack of proper applications that supports INDX files installed on the system. To address this issue, go to the Microsoft Mail developer website, download the tool, and install it. It is that easy The full list of programs grouped by operating systems can be found above. If you want to download Microsoft Mail installer in the most secured manner, we suggest you visit Microsoft Corporation website and download from their official repositories.

Step 2. Update Microsoft Mail to the latest version

If the problems with opening INDX files still occur even after installing Microsoft Mail, it is possible that you have an outdated version of the software. Check the developer’s website whether a newer version of Microsoft Mail is available. It may also happen that software creators by updating their applications add compatibility with other, newer file formats. This can be one of the causes why INDX files are not compatible with Microsoft Mail. 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 Mail.

Step 3. Associate Microsoft Mail Index files with Microsoft Mail

After installing Microsoft Mail (the most recent version) make sure that it is set as the default application to open INDX 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 INDX file and choose Open with option
  • Next, select the Choose another app option and then using More apps open the list of available applications
  • Finally select Look for another app on this PC, point to the folder where Microsoft Mail is installed, check the Always use this app to open INDX files box and conform your selection by clicking OK button

Selecting the first-choice application in Mac OS

  • Right-click the INDX file and select Information
  • Find the Open with option – click the title if its hidden
  • Select Microsoft Mail and click Change for all...
  • A message window should appear informing that This change will be applied to all files with INDX extension. By clicking Continue you confirm your selection.

Step 4. Verify that the INDX is not faulty

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

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

Should it happed that the INDX is infected with a virus, this may be that cause that prevents you from accessing it. Immediately scan the file using an antivirus tool or scan the whole system to ensure the whole system is safe. If the scanner detected that the INDX file is unsafe, proceed as instructed by the antivirus program to neutralize the threat.

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

If the INDX file was sent to you by someone else, ask this person to resend the file to you. The file might have been copied erroneously and the data lost integrity, which precludes from accessing the file. If the INDX file has been downloaded from the internet only partially, try to redownload it.

3. Ensure that you have appropriate access rights

Some files require elevated access rights to open them. Log out of your current account and log in to an account with sufficient access privileges. Then open the Microsoft Mail Index file.

4. Check whether your system can handle Microsoft Mail

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

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

Regularly updated system, drivers, and programs keep your computer secure. This may also prevent problems with Microsoft Mail Index files. It is possible that one of the available system or driver updates may solve the problems with INDX files affecting older versions of given software.

Do you want to help?

If you have additional information about the INDX 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 INDX file.

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