[Fix] Microsoft Outlook Cannot Preview PDF Attachments

Microsoft Outlook has attachment preview support wherein you can preview the file attachments without having to open the respective program. For this, Outlook utilizes the existing preview handler modules added by individual programs.

This article describes the various type of PDF attachment preview issues that users face in Microsoft Outlook/Outlook 365, and outlines the fixes for each type of issue.

Editor’s note: The PDF preview issues are usually caused if the installed Office/Outlook version is 32-bit, but your PDF reader is 64-bit. This issue seems to arise with a recent update of your PDF reader application (e.g., Acrobat Reader DC) from 32-bit to 64-bit. In this article, let’s see every typical PDF preview issue users face.

Symptoms

When you attempt to preview a PDF attachment in Microsoft Outlook, one of the following issues may occur:

1. The following error occurs when you click on a PDF attachment:

   This file cannot be previewed because there is no previewer installed for it.

   

2. Or, the following error occurs:

   This file cannot be previewed because of an error with the following previewer
   
   [preview handler name]

   

3. Nothing may happen when clicking on the PDF attachment. No error.
4. Or, the following error occurs:

   This file cannot be previewed because the following previewer has been disabled:
   
    [preview handler name]

[Fix] Microsoft Outlook Cannot Preview PDF Attachments

Case 1:  This file cannot be previewed because there is no previewer installed for it

This error denotes that no PDF viewer application has been installed on the computer. Many PDF viewer programs include a PDF preview handler module (DLL) that provides PDF preview capabilities in File Explorer and Microsoft Outlook.

You can fix this issue by installing a PDF viewer software like Adobe Reader, Foxit Reader, SumatraPDF, etc. For more information, check out the steps listed in the article PDF Thumbnail/Preview not working.

What if I have a PDF reader installed, and yet this happens?

If you’ve already installed a PDF viewer and preview capabilities are working fine on File Explorer (but not in Outlook), then it could be the bitness of your Office installation.

Let’s say you have installed the 32-bit version of Microsoft Office (on 64-bit Windows), and your viewer is a 64-bit application. In that case, previews for PDF files won’t work in Outlook.

• Office 32-bit  & PDF reader 32-bit  →  Preview will work.
• Office 32-bit  & PDF reader 64-bit  →  Preview will NOT work (unless the preview handler is registered under WOW6432Node in the registry).
• Office 64-bit  & PDF reader 32-bit  →  Preview will work.
• Office 64-bit  & PDF reader 64-bit  →  Preview will work.

Is your Office 32-bit or 64-bit?

To check the bitness of your Office installation, click on the File menu, select “Office account,” and click the “About Outlook” button.

You can check the bitness (32-bit or 64-bit) in the About box.

I have 32-bit Office. What should I do now?

• Solution 1: If you’re running 32-bit Office, you may uninstall it and install the 64-bit version. See Microsoft article Choose between the 64-bit or 32-bit version of Office for assistance.
• Solution 2: (For products other than Adobe:) If your PDF viewer is 64-bit, uninstall it and install the 32-bit version of the program. Unless you need to open huge PDF files (in gigabytes) as part of your official work, the 32-bit version of the PDF viewer should suffice. [Exception: For Microsoft PowerToys’s PDF previewer, there is an Outlook 32-bit registry fix available that will resolve the error “This file cannot be previewed because there is no previewer installed for it” in Outlook.]
• Solution 3: If you’re using Adobe Reader, the issue should rectify automatically if you update to the latest version of Adobe Reader. The latest version incorporates the registry fix (below) that enables PDF preview for Outlook 32-bit (even if Adobe Reader 64-bit is installed).
  Editor’s note: In September 2021, an Adobe staff confirmed that the following registry fix would be integrated with the next quarterly update of Acrobat/Reader so that users won’t have to run this file manually. I can confirm that the following registry fix has been incorporated into the latest version of Adobe Acrobat Reader DC — version 2021.007.20099 as of this writing. Please update the program if you don’t have the newest version.

  However, if you wish to apply the registry file manually, copy the following lines to Notepad and save the file as PreviewFix.reg. Then double-click the file to run it. Click Yes (when prompted) to apply the settings. For more information about registry files, check out the article How to use .REG files (Registration Entries) in Windows.

  Windows Registry Editor Version 5.00
  
  [HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Classes\CLSID\{DC6EFB56-9CFA-464D-8880-44885D7DC193}]
  "DisplayName"="@C:\\Program Files\\Adobe\\Acrobat DC\\Acrobat\\pdfprevhndlr.dll,-101"
  "AppID"="{6d2b5079-2f0b-48dd-ab7f-97cec514d30b}"
  @="Adobe PDF Preview Handler for Vista"
  "DisableLowILProcessIsolation"=dword:00000000
  
  [HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Classes\CLSID\{DC6EFB56-9CFA-464D-8880-44885D7DC193}\InprocServer32]
  "ThreadingModel"="Apartment"
  @="C:\\Program Files\\Adobe\\Acrobat DC\\Acrobat\\pdfprevhndlr.dll"
  
  [HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Classes\CLSID\{DC6EFB56-9CFA-464D-8880-44885D7DC193}\ProgID]
  @="PDFPrevHndlr.PDFPreviewHandler.1"
  
  [HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Classes\CLSID\{DC6EFB56-9CFA-464D-8880-44885D7DC193}\TypeLib]
  @="{0F6D3808-7974-4B1A-94C2-3200767EACE8}"
  
  [HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Classes\CLSID\{DC6EFB56-9CFA-464D-8880-44885D7DC193}\VersionIndependentProgID]
  @="PDFPrevHndlr.PDFPreviewHandler"

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Case 2: This file cannot be previewed because of an error with the following previewer

The error “Error with the following previewer” occurs if the PDF preview handler is registered correctly but the corresponding file is missing. In that case, reinstalling the PDF viewer program can resolve the issue.

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Case 3: Nothing happens when you click on the PDF attachment in your email.

If nothing happens when you click on a PDF file attachment in your email, the attachment preview feature may have been turned off.

1. Click on the File menu in Outlook, and click Options.
2. Click “Trust Center,” and click Trust Center Settings… button
3. Click “Attachment Handling”
4. Uncheck the option named “Turn off Attachment Preview.”
   
5. Optionally, click the “Attachment and Document Previewers…” button and check if your PDF preview handler is listed in the “File Previewing Options” dialog.
   Each PDF reader application uses a different caption (e.g., “Pdf Preview Handler” by Microsoft PowerToys, “Adobe PDF Preview Handler for Vista” by Adobe Acrobat Reader, “Foxit PDF Preview Handler” by Foxit Reader, “SumatraPDF Preview” by SumatraPDF viewer, etc.) for the preview handler.
   Note that Microsoft Edge’s preview handler is also shown by the same name (“PDF Preview Handler”) as Microsoft PowerToys’s, but PowerToys uses the title case — “Pdf” vs “PDF”. Note that in the recent versions of Microsoft PowerToys, PDF preview is disabled by default, as Windows already uses Microsoft Edge Chromium’s PDF handler.

   

   Note that if your PDF preview handler is a 64-bit module, Office/Outlook 32-bit will not list the PDF preview handler in the “File Previewing Options” dialog. If you’re using Microsoft PowerToys for PDF previews, then you’ll need to apply a registry fix (Outlook 32-bit Registry Fix for Microsoft PowerToys users) that the module can work in Outlook 32-bit.

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Case 4: This file cannot be previewed because the following previewer has been disabled

This message is self-explanatory, and all you need to do is enable the module by clicking on the “Enable” button underneath. Alternately, you can open the TrustCenter settings and enable the PDF preview handler via the “File Previewing Options” dialog.

I hope you could resolve Outlook PDF preview issues using one of the above methods. Let’s know your comments.