Fix This File Cannot Be Previewed Outlook Error

A number of Outlook users have reported that they were unable to preview MS Excel and other attachments on their Outlook account. When they tried to do so, an error message prompts, i.e.This file cannot be previewed as there is no previewer installed for it. Here are few methods to fix this issue.


Method 1: Ensure that Required Applications are installed

Make sure that applications used to open the file or attachment are installed. Example: Word for documents, Excel for spreadsheets etc.

Method 2: Check the Attachment Handling Settings

  • Open the Outlook application
  • Go to File->Options -> Trust Center-> Trust Center Settings -> Attachment Handling
  • Make sure that “Turn Off Attachment Preview” is Not checked
  • Then select the “Attachment and Document Previews” button
  • Ensure that the previewer you want to use is checked (Marked)
  • Then click OK for every window (Hit OK 3 Times)

Method 3: Fix Windows Registry

  • Click Windows Key + R combination, in the Run dialog box type regedit and hit Enter to open the Registry Editor
  • In the left pane of Registry Editor, navigate to the following path:
  •             HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\15.0\Word\Options\Assist

  • Then right-click on Assist key and then select Delete option. (The issue occurs if this key is present, so we need to delete it)
  • Close the Registry Editor and reboot the system, then you can see that Outlook is able to preview files without any problem.

Note: Any mistakes while manipulating Registry could affect the computer badly or corrupt it. The corruption that occurs to registry database can also damage Outlook OST file. So, in that case, you must convert OST to PST in Outlook 2013, 2016, 2010, 2007, 2003 and Outlook 2000. To do that you can make use of Convert OST to PST software.

Procedure to Fix This File Cannot Be Previewed Outlook Error :

Step 1: - Download and install the Convert OST to PST application on your system. Once you launch the program, the upcoming window shows two options namely “Open OST File” and “Find OST File”. If the OST file location is known to you then select the first option or else go with the second option.

How to Convert OST to PST in Outlook 2013 - Home Screen

Figure 1: Home Screen


Step 2: If you have selected “Find OST File” option then a new window will appear from where you can locate the OST file using “Find” button. Once the OST file is located click on the Next button to proceed further.

How to Convert OST to PST in Outlook 2013 - Find OST File

Figure 2: Find OST File


Step 3: Then select the desired location to save the converted file. Then click on Convert

How to Convert OST to PST in Outlook 2013 - Path of Converted Files

Figure 3: Path of Converted Files

Step 4: Lastly, click on the Finish button to end the process.

How to Convert OST to PST in Outlook 2013- Final screenshot

Figure 4: Final Stage

Tip: To avoid this situation in the future, make sure that all the necessary applications to open attachments are installed and are updated in your system