Fix Unable to Open Outlook Attachment
Updated on June 26, 2025 by Armaan
Microsoft Outlook is a powerful email client, but sometimes it prevents users from opening email attachments. When double-clicking doesn’t work, and even restarting Outlook doesn’t help, it can be frustrating. You might see an error like “Unable to Open Outlook Attachment.”
But don’t worry—this guide covers easy steps to resolve the issue and regain access to your attachments. Keep reading to learn more.
But before getting to know the solutions, it is necessary to learn about some important things.
In this Artical
What exactly is an email attachment?
The term itself is rather an identity. This is more than simply an email attachment delivered with a message. This is a basic method for sharing documents and photographs. Email attachments can be used to distribute one or even more files. Emails are mainly text files, but when attachments are added, they become numeric or structured files.
Why can't you view attachments in Outlook?
Email attachments are among the most valuable assets to an organization since they can be used to send invoices and other critical information. A few of the reasons why you can't access Outlook attachments are as follows:
Totally corrupted files: When viewing a mail attachment in Microsoft Outlook, a warning notice appears that states, "the file is corrupted and cannot be opened." This implies the sender must check to see if the email attachment is operating correctly on their side, and if it isn't, the sender must resend it.
Unexpected characters: In the file title If a mail attachment has a question mark and a plus sign in the document name, the user is unable to access the information.
Faulty add-ins: If you are using MS Outlook and are unable to view a document attachment, you may have to deactivate add-ins. Whether you are not really aware how, then follow the directions below.
- Press File > Options > Add-ins in Microsoft Outlook.
- Under Manage, choose COM Add-ins and then press "GO."
- Disable all of the add-ins now.
- When all add-ins have been deactivated, click "OK."
- Lastly, shut and re-open Microsoft Outlook, and then download the associated file once more.
This usually prevents users from opening attachments to email files in invalid file formats. To view the extension with the appropriate format extension, one must obtain the specific program.
A person may be unable to access attachments for one of two reasons: either the file linked is incorrect, or there is an issue with the software that requires the attachment to load.
Manual Ways to Fix Unable to Open Outlook Attachment Error
Experts have found some legit solutions to this error. Keep reading Below, we have added Four effective manual methods to resolve the Unable to Open MS Outlook Attachment error.
Method 1: Set Microsoft Email as the default email address
If you are incapable of reading Microsoft Outlook attachments and receive an "access is denied" message, it is probable that you have made a non-Microsoft email account your default email address. Perform these procedures to convert your default email account to your Microsoft email account:
- Sign in to your Microsoft account on the Microsoft account webpage.
- Navigate to your information and then press the "Submit" button. Adjust your sign-in email address or phone number.
- Enter a Microsoft email address in the Make main section.
Method 2: Open the attachment by right clicking on your mouse
If double-clicking Outlook attachments does not open them, you might try an alternative technique. You may open an attachment by right-clicking it rather than double-clicking it.
The main reason why double-clicking an attachment does not function for certain people is the mouse's double-click frequency. If your mouse's double-click velocity is increased, you may fail to access attachments by double-clicking them. You may manually slow down the double-click speed by navigating to the Control Panel, then Mouse, and then Buttons.
Method 3: Update to the latest version of your Outlook
If you are unable to open attachments in Outlook, you may be missing certain critical Outlook updates. Follow these procedures to install the most recent Outlook updates:
- Pick the File tab in Microsoft Outlook.
- Press the Update Options button on the Office Account page.
- Choose Update Now from the menu bar.
- Lastly, restart Outlook.
Method 5: Clear the Outlook Temporary Files Folder
Outlook stores attachment previews in a hidden temp folder that may get corrupted for various reasons. Try this maybe it will works.
1. Press Win + R → Type: %localappdata%\Microsoft\Windows\INetCache\Content.Outlook\
2. Open the folder(s) inside and delete all files.
3. Restart Outlook and try opening attachments again.
Method 6: Check Outlook’s Attachment Handling Settings
Sometimes attachment preview is disabled or blocked by policy.
- Open Outlook > File > Options > Trust Center.
- Click Trust Center Settings > Attachment Handling.
- Uncheck Turn off Attachment Preview.
- Also, click Attachment and Document Previewers to enable specific formats.
Method 7: Use Professional tool to Fix Unable to open attachments in Outlook error
If you are still struggling to view attachments in Outlook after attempting the options listed above, investigate the PST file's condition. If your Outlook data file (PST) is faulty, this might be the cause of your inability to access attachments. The Inbox Repair Tool, which is available in the default Outlook configuration file, may be used to fix the file.
But sometimes it happens that the built-in PST repair tool fails to fix it. At that time, you can use a powerful PST file repair tool.There are numerous tools accessible on the internet for this goal. Regain Outlook PST Repair is one of them. You can use it.
The benefits of using the Regain Outlook PST Repair Tool
Using this tool, you can easily retrieve your inaccessible and lost mailbox items. It has the facility to recover permanently deleted emails. Using this software, you can fix any additional issues caused by a corrupted PST file.
However, if somehow you need to recover your deleted PST files, then this software is for you. Besides repairing a PST file, it can also complete some additional tasks, which are more effective benefits of this tool. Actually, the best thing about the software that you are going to love is its simple and excellent interface.
Frequently Asked Questions
Q 1. Why can’t I open attachments in Microsoft Outlook?
Ans. You might be facing this issue due to a corrupt temporary folder, incorrect file association, blocked file types, or Outlook profile corruption.
Q 2. How do I fix the 'Unable to Open Outlook Attachment' error manually?
Ans. Try clearing Outlook's temp folder, repairing file associations, disabling antivirus email scans, or saving the attachment locally before opening.
Q 3. What to do when Outlook attachments won’t open even after restarting?
Ans. Restarting may not resolve deeper issues. Try repairing Outlook settings or using the Regain Outlook Repair Tool to fix corrupt Outlook data files.
Q 4. Why are PDF or Word attachments not opening in Outlook?
Ans. This could be due to file association issues or previewer settings in Outlook. Ensure the correct default app is set for each file type.
Q 5. How to fix Outlook attachments blocked by antivirus software?
Ans. Temporarily disable email scanning features in your antivirus software and try opening the attachment again.
Q 6. Can corrupted Outlook files cause attachment issues?
Ans. Yes, if your PST or OST file is corrupted, Outlook may fail to open attachments. Use Regain Outlook Repair Tool to scan and repair your data file.
Q 7. How do I repair my Outlook data file to resolve attachment issues?
Ans. You can use the built-in ScanPST tool, or for better results, try Regain Outlook Repair Tool, which offers deeper repair and full data recovery.
Q 8. What’s the easiest way to fix attachments not opening in Outlook?
Ans. Save the attachment to your desktop and open it manually. If the problem persists, repairing your Outlook profile or using a tool like Regain Outlook Repair Tool can help.
Q 9. How can Regain Outlook Repair Tool help with attachment issues?
Ans. The Regain Outlook Repair Tool repairs corrupted PST/OST files, which often resolves hidden errors that prevent attachments from opening properly.
