4 Ways to Outlook File Cannot Be Previewed Error

Outlook users often encounter different errors while trying to open the application, accessing any emails or attached files to them. Such errors occur due to some fault or corruption in the Outlook settings and database files. The purpose of this blog is to deliver apt solutions to users who are facing “Outlook File Cannot Be Previewed Error” issue on attempt to access the attached files within their email.

The error says the file cannot be opened and previewed now and thus restricts users to view the attachment.

Frequent Reasons for Outlook File Cannot Be Previewed Error

It is important to understand the main reasons which can be responsible for this error so as to prevent it in the future by any means. Know about some potential causes behind “Fix Outlook File Cannot Be Previewed Error” error.

  • The file preview application is not installed on the system
  • Inaccurate Windows Registry settings
  • Incorrect Outlook attachment handling settings
  • Windows Firewall is disabled on the system
  • Issues in preview application settings

Have a Try on These Manual Solutions

Our recommended manual solutions are based on the assumptions of the causes behind the error and can be at least tried by users to get out of the situation to open and preview the attached files in the Outlook email.

Confirm the installation of Viewer application

The error itself indicates that the viewer application is not available or installed. So, you must ensure that the files previewer application is installed on your system. For example – to access and view PDF files, you must have a PDF Reader application installed on your system. So, once you install the related application on your system, your problem can get resolved.

Modify Windows Registry Settings

If you have the files previewer application already installed on your system or even after installing the same, getting the error, then the problem is something else. It can be due to a missing or corrupt Windows Registry. Check out the following procedure to resolve the issue.

  1. On a notepad, paste this registry value as it is.
    Windows Registry Editor Version 5.00
  2. Save the file with a .reg extension to make it a registry file on your system drive location.
  3. Now, double click this file to run this value and setting to make it into effect.
    Or in the Registry Editor, you can navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Classes\CLSID\{DC6EFB56-9CFA-464D-8880-44885D7DC193},
    Click on the AppID and then modify the value to – {534A1E02-D58F-44f0-B58B-36CBED287C7C} in the opened dialogue box. Click OK and exit the Registry Editor.
  4. Restart the system and then try accessing the Outlook attachment to check the difference.
    Turn ON Windows Defender Firewall on your System

Some users keep their Windows Defender Firewall feature turn OFF to fix other issues. But, sometimes enabling this feature can help Outlook users to access the attachment files well. Use these steps to turn ON Windows Firewall on your system.

  1. On your system navigate to Start>Settings>Update & Security>Windows Security>Firewall & Network Protection.
  2. Select a profile for the network, go to the Windows Defender Firewall section on your system and slide the bar to turn ON the settings.
  3. Restart the system and check upon Outlook email attachments if accessible or not.

Modify Microsoft Application Option

If your Office files are in attachments and cannot be previewed in the Outlook interface, a workaround is available which you can try on your own. We are assuming the attachment file is a MS Word file.

  1. Launch the MS Word application on your system.
  2. Click on the File menu and select Options.
  3. On the Word Options page, click General from the left panel.
  4. On the right panel, go to the User Interface options section and select the second option “Optimize for compatibility (application restart required)” under it.
  5. Now restart the application.
  6. Open the Outlook email and check if the attachment file can be previewed.

Check upon Attachment Handling Settings in Outlook

Inaccurate Outlook attachment handing settings in the application could be the cause behind the inability of the user to preview their Outlook email attachments. Let us know how we can correct this setting.

  1. Launch the Microsoft Outlook application.
  2. Click on the File menu and select Options.
  3. Now, from the left panel, click on the Trust Center option and then on the right panel, click on the Trust Center Settings option.
  4. A new window namely Trust Center will get opened. Click Protected View option from the left panel.
  5. On the right panel, make sure that the third option “Enable Protected View for Outlook attachments” under the Protected View section is unselected or unchecked. If selected, then uncheck it.
  6. Close the application and then restart it.
  7. Open the Outlook email and try to open the attachment now.

All these manual workarounds are feasible and not so difficult to perform. Rather users can get success in resolving the “Fix Outlook File Cannot Be Previewed Error” error by adopting one or more of the above solutions.

There are many other Outlook errors faced by users on trying to access the application and inbox itself. Most of which occurs due to corruption in the Outlook database (PST) file. Such corruption in PST file is possible due to many factors like oversize file, sudden application or system shut down, malicious links, bugs, third-party applications influences, etc. So, try a professional utility like PST Repair tool fix all corrupted related problems in your Outlook database file automatically without any loopholes and with full results. The tool is capable to recover data even the deleted items easily from the highly corrupted files easily. One can assure about it by working on the free trial version.

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Outlook attachments are not accessible is another tension which can occur if the previewer application not installed or missing registry, or incorrect Outlook settings. In this blog, related solutions are provided with necessary steps to fix Outlook File Cannot Be Previewed Error forever and additionally a smart tool is suggested for treating corrupt PST files efficiently.

About Barrett Clay

Barrett is passionate about technology and an admirer who believes in offering instant computing solutions to everyone. He solves personal and business technical issues related to IT products, applications, IT environments, platforms, technologies, etc., through well-documented blogs and articles, informative, authentic and descriptive content. He participates in technical content development, content publishing and marketing.

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