MS-TNEF file icon

MS-TNEF File Extension

MS Transport Neutral Encapsulation Format
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What is MS-TNEF file?

MS-TNEF is a file extension commonly associated with MS Transport Neutral Encapsulation Format files. Microsoft defined the MS Transport Neutral Encapsulation Format format standard. Files with MS-TNEF extension may be used by programs distributed for Mac OS, Windows platform. MS-TNEF file format, along with 6033 other file formats, belongs to the Misc Files category. Users are advised to use Microsoft Outlook software for managing MS-TNEF files, although 2 other programs can also handle this type of file. On the official website of Microsoft Corporation developer not only will you find detailed information about theMicrosoft Outlook software, but also about MS-TNEF and other supported file formats.

Programs which support MS-TNEF file extension

The following list contains programs grouped by 2 operating systems that support MS-TNEF files. MS-TNEF files can be encountered on all system platforms, including mobile, yet there is no guarantee each will properly support such files.

Programs that support MS-TNEF file

How to open file with MS-TNEF extension?

Problems with accessing MS-TNEF may be due to various reasons. On the bright side, the most encountered issues pertaining to MS Transport Neutral Encapsulation Format 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. Get the Microsoft Outlook

Install software to open MS-TNEF file Problems with opening and working with MS-TNEF files are most probably having to do with no proper software compatible with MS-TNEF files being present on your machine. This issue can be addressed by downloading and installing Microsoft Outlook or different compatible program, such as Apple Mail. The full list of programs grouped by operating systems can be found above. One of the most risk-free method of downloading software is using links provided by official distributors. Visit Microsoft Outlook website and download the installer.

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

Update software that support file extension MS-TNEFYou still cannot access MS-TNEF files although Microsoft Outlook 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. This can be one of the causes why MS-TNEF files are not compatible with Microsoft Outlook. 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 Outlook.

Step 3. Associate MS Transport Neutral Encapsulation Format files with Microsoft Outlook

After installing Microsoft Outlook (the most recent version) make sure that it is set as the default application to open MS-TNEF files. The method is quite simple and varies little across operating systems.

Associate software with MS-TNEF file on Windows

Selecting the first-choice application in Windows

  • Choose the Open with entry from the file menu accessed by right-mouse clicking on the MS-TNEF file
  • 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 Outlook is installed, check the Always use this app to open MS-TNEF files box and conform your selection by clicking OK button
Associate software with MS-TNEF file on Mac

Selecting the first-choice application in Mac OS

  • From the drop-down menu, accessed by clicking the file with MS-TNEF extension, select Information
  • Open the Open with section by clicking its name
  • Select Microsoft Outlook and click Change for all...
  • A message window should appear informing that This change will be applied to all files with MS-TNEF extension. By clicking Continue you confirm your selection.

Step 4. Ensure that the MS-TNEF 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 MS-TNEF file. Being unable to access the file can be related to various issues.

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

Should it happed that the MS-TNEF 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 MS-TNEF file is unsafe, proceed as instructed by the antivirus program to neutralize the threat.

2. Verify that the MS-TNEF file’s structure is intact

If you obtained the problematic MS-TNEF file from a third party, ask them to supply you with another copy. During the copy process of the file errors may occurred rendering the file incomplete or corrupted. This could be the source of encountered problems with the file. When downloading the file with MS-TNEF 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 out of your current account and log in to an account with sufficient access privileges. Then open the MS Transport Neutral Encapsulation Format file.

4. Make sure that the system has sufficient resources to run Microsoft Outlook

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

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

Latest versions of programs and drivers may help you solve problems with MS Transport Neutral Encapsulation Format files and ensure security of your device and operating system. It may be the case that the MS-TNEF files work properly with updated software that addresses some system bugs.

Do you want to help?

If you have additional information about the MS-TNEF 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 MS-TNEF file.

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