Can’t able to open attachments in Outlook? – Try these fixes

Outlook may show messages like “Error downloading the file content” or “We couldn’t open the file” when trying to open attachments, especially in the New Outlook app or shared mailboxes. This means that the app cannot get the attachment because of sync problems, permission limits, or bad cache data.

The most common cause is a broken or too full Outlook cache, with other reasons including wrong mailbox time zone settings or turned-off add-ins. In some cases, Protected View rules or limits on temporary file access can also stop attachments from opening.

1. Check for Internet Connectivity

If your internet connection is slow or unstable, the attachment may not load and open. Try switching to a different network or to the 5 GHz band on your Wi‑Fi for faster speeds.

You can also restart your router. Press the power button on the back of the router to turn it off, wait a few seconds, and turn it back on. Once it restarts, check if your internet is stable.

If possible, use an Ethernet cable instead of Wi‑Fi. A wired connection is usually more stable and can prevent interruptions.

2. Check for Compatibility Issues

You may not be able to open an attachment in Microsoft Outlook if the file type isn’t recognized by your computer. Ask the sender to resend the attachment in a common format your apps can open (for example, PDF, DOCX, XLSX, JPG, or PNG).

3. Make Outlook Email Address As Primary Email Address

If you have multiple accounts in Outlook, set the account you use to receive the attachment as the default.

1. Select Account Settings under File and then click on Account Settings.

   

2. Choose the account you want to use as the default on the Email tab.
3. Now, select Set as Default and then Close.

4. Clean Outlook Cache Files

Sometimes Outlook’s cache gets corrupted and causes issues with opening attachments.

1. Press the Windows + R keys to open the Run dialog box.
2. In the Run box, type the following and press Enter:

   %localappdata%\Microsoft\Outlook\RoamCache

   

3. The RoamCache folder opens in File Explorer.
4. Select all the files in this folder and click the Trash/Delete icon to remove them.

   

5. Update Microsoft Outlook

If Outlook won’t open attachments, you might be missing important updates. Updating Outlook can improve stability, security, and fix bugs that cause this issue.

1. Open Microsoft Outlook and click the File tab.
2. Click Update Options under the Office Account tab.
3. Then choose Update Now.

   

4. When the update finishes, restart Outlook.

6. Disable Outlook Add-Ins

Some Outlook add-ins can conflict with attachments. Disable them one by one to find the culprit.

1. Launch Microsoft Outlook and click on File, then on Options.
2. Click on Add-ins.

   

3. Under Manage, select COM Add-ins and press Go.
4. Uncheck each add-in to disable it.

   

5. Click OK, then restart Outlook and test opening the attachment. Re-enable add-ins one at a time to identify the problematic one.

7. Disable Antivirus Software

Antivirus software can sometimes flag safe files by mistake and block them. If you still can’t open attachments, your antivirus might be interfering with Outlook.

Temporarily turn off your antivirus and try again. Remember to turn it back on afterward.

7.1 Microsoft Defender

1. Press Win + I to open Windows Settings.
2. Go to Privacy & Security > Windows Security > Virus & threat protection.

   

3. Click Manage settings under Virus & threat protection and turn off Real-time protection.

   

4. Try opening the attachment again. Turn protection back on when you’re done.

7.2 Third-party virus protection:

1. Open your third-party antivirus program and go to Settings.
2. Find the Protection section, temporarily disable protection, and save your settings.

   

3. Check whether you can open the attachment now. Re-enable protection afterward.

8. Check Outlook Attachment Handling Settings

If attachment preview is turned off, you might not be able to open attachments directly in Outlook.

1. Open Outlook and click the File menu.
2. Select Options, go to the Trust Center tab, and click Trust Center Settings.

   

3. On the Attachment Handling tab, make sure Turn off Attachment Preview is unchecked.

   

4. Click Attachment and Document Previewers and ensure the previewers you need are enabled.

   

Reboot Microsoft Outlook and try to open the attachment to see if the problem is fixed or not.

9. Run scanpst.exe Tool

If the issue persists, run Outlook’s built-in Inbox Repair Tool (scanpst.exe). It can repair corrupted Outlook Data (.ost) and Personal Folders (.pst) files.

1. Press Windows + E to open File Explorer and go to:

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

2. Double-click SCANPST.EXE to open it.

   

3. Click Start to begin the scan and repair process, then follow the prompts.