FIX: Cannot Preview EXCEL Files in Outlook 2016

Outlook may show “This file cannot be previewed because there is no previewer installed for it” while you try to preview an Excel attachment in the reading pane. This means Outlook can’t find or run the Excel preview tool, even if Excel is installed.

The most common cause is a missing or wrong Windows Registry entry for the Excel Previewer (GUID {00020827-0000-0000-C000-000000000046}). Other causes include corrupted registry strings or a broken Click-to-Run path in Microsoft 365.

1. Correct Windows Registry Entry

If a registry setting is broken or set up wrong, Outlook can’t find Excel’s preview tool. Fixing that setting restores the correct path, so Outlook can find and use the Excel previewer to show attachment previews.

1. Press and Hold the Windows key, then Press R. The Run dialog box will appear.

2. Type regedit and press Enter. Click Yes if a User Account Control confirmation message appears.

3. In the left pane, Double Click on HKEY_LOCAL_MACHINE to expand it. Under it, similarly Double Click on Software to expand it.

4. Now, the navigation path from here will differ based on the type of Microsoft Office you have installed and the bitness (32-bit or 64-bit) of Microsoft Office and Windows. If you are not sure about the bitness or the type of product, you can try all of the paths below. If you cannot find the next folder while following a certain path, simply move on to the next path.

5. If you have installed the Click-to-Run version of Microsoft Office, which is the case for most users, then follow this path:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\ClickToRun\REGISTRY\MACHINE\Software\Microsoft\Windows\CurrentVersion\PreviewHandlers

6. If you have installed a 32-bit version of Microsoft Office on a 64-bit Windows, then follow this path:

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\PreviewHandlers

7. If you have a 64-bit version of Microsoft Office on a 64-bit Windows (or you are on 32-bit Windows), then follow this path:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\PreviewHandlers

8. Once you have Selected (Highlighted) PreviewHandlers in the left pane, you will see a number of registry strings in the right pane. We only need four of them.

9. On the right, you will see three columns: Name, Type and Data. In the Name column, look for the four strings with the following names and make sure the corresponding value in Data is exactly the same as written below.

Name                                                                                                                Data

{21E17C2F-AD3A-4b89-841F-09CFE02D16B7}                      Microsoft Visio previewer

{65235197-874B-4A07-BDC5-E65EA825B718}                      Microsoft PowerPoint previewer

{84F66100-FF7C-4fb4-B0C0-02CD7FB668FE}                        Microsoft Word previewer

{00020827-0000-0000-C000-000000000046}                        Microsoft Excel previewer

10. If any value differs, then Double Click the incorrect string to Modify it.

11. In the box under Value Data, Erase the old value and Type the correct value according to the list above. Then Click OK.

12. If more than one string has an incorrect value, correct them all.

13. If the registry strings are missing entirely, then Right Click in the right pane and Click New, and then click String Value. Name the registry string according to the list above.

14. After that, Double Click the registry string to Modify it and Type the Value Data according to the list above. Repeat the process for the other 3 strings too.

15. Now Restart your computer and check if the issue is resolved. If not, tell us your exact situation in the comments section and we will get right to it.