Outlook blocked access to the following potentially unsafe attachments

If You may see a message in Outlook 2016 that outlook has blocked access to certain attachments. This is because these attachments have the potential to be malware files. While this is a good security measure, there may be times when you need to temporarily disable this warning feature and unlock the attachment. If this is the case, this post will help you.

Outlook blocked access to the following potentially unsafe attachments

This could help if you need that file right now and you trust the sender.

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Unblock blocked Outlook attachment

To be able to download files from Outlook, you need to add a special value in the Registry file. It is recommended to create a system restore point and backup the Registry files before getting started.

To access the Registry Editor, press Win + R to open the Run prompt and type Regedit. After that, navigate to this path:

HKEY_CURRENT USER\Software\Microsoft\Office\16.0\Outlook\Security

This path is for Outlook 2016 users. However, if you are using an older version, this path would be different, like this-

Outlook 2013:

HKEY_CURRENT USER\Software\Microsoft\Office\15.0\Outlook\Security

Outlook 2010:

HKEY_CURRENT USER\Software\Microsoft\Office\14.0\Outlook\Security

If you do not see your Outlook version number (e.g., 16.0 or 15.0) listed under the “View” options, you will need to create it manually. To do so, follow these steps:

HKEY_CURRENT USER\Software\Microsoft\

Right-click on Microsoft > New > Key. Name it as Office. Now, right-click on Office > New > Key and name it as follows-

  • Outlook 2016: Type 0
  • Outlook 2013: Type 0
  • Outlook 2010: Type 0

You can now right-click on the “16.0/15.0/15.0” key in the Registry Editor and select “New” > “Key”. Name this key as “Outlook”. After that, right-click on the newly created “Outlook” key and select “New” > “Key” again. Name this key as “Security”.

Next, right-click on the “Security” menu item, select “New” > “String Value”, and name it “Level1Remove”. Now, double-click on this string value and enter the following value:


If you enter this value, Outlook will show the .exe and .msi files in your email. However, if you want to include only .msi file support, you can add this value.

After saving and restarting Microsoft Outlook, you will be able to find your file in your email that was previously blocked by this email client.

We strongly recommend that you use this method temporarily. After downloading the file from your email, you can remove the value you have created and that way you will be on the safe side.

Read Also: How to Sync Your iPhone With Outlook Email ?

The Attachment Manager in Windows lets you configure High risk, Medium risk, Low risk files according to their potential threat.

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