You can't preview Word documents in Outlook 2013

Applies to: Outlook 2013


You have Microsoft Office 2013 installed, and you try to preview a Microsoft Word document in Microsoft Outlook 2013. In this situation, you receive the following error message:

This file cannot be previewed because of an error with the following previewer:
Microsoft Word previewer
To open this file in its own program, double-click it.


This problem occurs when the system registry contains the following subkey:
When the registry contains this subkey, Outlook cannot preview a Word document.


Important Follow the steps in this section carefully. Serious problems might occur if you modify the registry incorrectly. Before you modify it, back up the registry for restoration in case problems occur.

To fix this issue, delete the Assist subkey from the registry. To do this, follow these steps:
  1. Exit Outlook.
  2. Start Registry Editor. To do this, use one of the following procedures, as appropriate for your situation:
    • Windows 10, Windows 8.1 and Windows 8: Press Windows Key + R to open a Run dialog box. Type regedit.exe and then press OK.
    • Windows 7 or Windows Vista: Click Start, type regedit.exe in the search box, and then press Enter.
  3. Locate and then click the following subkey:
  4. Right-click the Assist key, and then click Delete.
  5. When you are prompted to confirm the deletion, click Yes.
  6. On the File menu, click Exit to exit Registry Editor.

More Information

The HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\15.0\word\options\assist path is used by Group Policy for proofing tools such as those that correct capitalization, replace text as you type, and insert smart quotes.