5 Fixes for Unable to Open Attachments in Microsoft Outlook on Windows

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• You should first check Outlook’s attachment handling settings to ensure file previewers are enabled.
• Disabling add-ins and clearing the app cache can also get Outlook to open your email attachments.
• If nothing works, you can consider repairing Outlook data files on your PC.

Fix 1: Check Attachment Handling Settings

If Outlook is unable to open your email attachments, it may be because the file previewer option is disabled. Here’s how to enable it.

Step 1: In the Outlook app, click the File menu in the top left corner.

Step 2: Select Options from the left sidebar.

Step 3: Switch to the Trust Center tab and click the Trust Center Settings button.

Step 4: In the Attachment Handling tab and uncheck the Turn off Attachment Preview checkbox.

Step 5: Click on Attachment and Document Previewers and make sure all the previewers are active. Then, hit OK.

Restart Microsoft Outlook after this and see if you can open attachments.

Fix 2: Open Microsoft Outlook in Safe Mode

When you open Microsoft Outlook in safe mode, the app runs without any add-ins. If a third-party Outlook add-in is causing trouble, using Outlook in safe mode will help you verify that.

To launch Outlook in Safe Mode, hold down the Ctrl key and double-click the Outlook shortcut. Click Yes when the confirmation prompt appears.

Now, check if Outlook can open attachments while in safe mode. If it can, one of the third-party add-ins could be to blame for the issue. You will need to disable all Outlook add-ins and then re-enable them one at a time to find the one causing the issue.

Step 1: Click on the File menu at the top and select Options.

Step 2: In the Outlook Options window, switch to the Add-ins tab. Use the drop-down menu next to Manage and select COM Add-ins. Then, click on the Go button.

Step 3: Uncheck all the boxes to disable add-ins and click on OK.

Restart Outlook in normal mode and enable your add-ins one by one to isolate the culprit.

Fix 3: Clear Outlook Cache

Corrupt Outlook cache data may also prevent the app from functioning normally. If that’s the case, clearing Outlook’s cache files should help.

Step 1: Press the Windows key + R to open the Run dialog.

Step 2: Type the following path in the Open field and press Enter:

%localappdata%\Microsoft\Outlook\RoamCache

Step 3: Select all the files inside the RoamCache folder and click the trash icon at the top to delete them.

Restart Outlook and inspect the mail attachments again.

Fix 4: Temporarily Disable Antivirus Program

Your antivirus software may prevent Outlook from loading or opening suspicious attachments. However, it can occasionally block legitimate files and cause issues. If you’re confident about the file source, you can disable your antivirus program temporarily and then try to open the attachment again.

Make sure you re-enable the antivirus program after viewing your attachments.

Fix 5: Use Outlook’s Data File Repair Tool

If you are still unable to open your email attachments, the issue could be related to Outlook data files on your PC. You can use Outlook’s Repair tool to fix the issue.

Step 1: Open File Explorer on your PC and navigate to the following folder.

C:\Program Files\Microsoft Office\root\Office16

Step 2: Double-click on the SCANPST.EXE file to open it.

Step 3: Click on Start to initiate the scan.

Step 4: If the tool finds any issues, click on Repair.

Reopen Outlook on your PC. Following this, you should be able to open attachments without any issues.