Embedded Objects are Blocked in Outlook Tasks

Last reviewed on August 8, 2012

Applies to: Applies to: Microsoft Outlook 2010 or Outlook 2007

A user complained that Outlook 2010 was blocking access to a Word document attachment he sent to a Task using Word's Create Outlook Task command.

I'm receiving this message in Outlook 2010 when opening a task created by Microsoft Word 2010:

"Outlook blocked access to the following potentially unsafe attachments"

I tried the Level1Remove registry fix but this did not work. I disabled Protected View (in Trust Settings) within Word. Still no go. Why is Outlook blocking attachments from its own software (Word)?

This security issue affects Outlook 2007 and up. The file is blocked because it's not a doc file, it's a *shortcut* to the doc file and shortcuts are potentially "dangerous".

Blocked shortcut to attachment

With the registry key set, the shortcut can be opened from the task. You need to configure the security settings to not block the file. In Outlook 2007 and Outlook 2010 you can use the following registry keys to change the Security settings. You'll need to restart Outlook for the keys to take effect.

Enabling ShowLevel1Attach will allow users to open or save potentially dangerous attachments. While an updated antivirus will catch older exploits if users try to save or open the attachment, it could miss new exploits not yet in it's virus definition file.

Outlook 2010

HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\14.0\Outlook\security
DWORD: ShowOLEPackageObj
Value: 1
DWORD: AdminSecurityMode
Value: 3
DWORD: ShowLevel1Attach
Value: 1

Outlook 2007

HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\12.0\Outlook\security
DWORD: ShowOLEPackageObj
Value: 1
DWORD: AdminSecurityMode
Value: 3
DWORD: ShowLevel1Attach
Value: 1

Do It For Me

I have a reg file to unblock all attachments and OLE objects. Save the text file with the extension .reg then run it. It works with non-Exchange accounts.

Network users may be blocked by group policy, so this should only be used by SOHO users - everyone else should speak to their admin.

ShowLevel1Attach2010ShowLevel1Attach-2007

You'll need to restart Outlook for the key to take effect.

Written by

Diane Poremsky
A Microsoft Outlook Most Valuable Professional (MVP) since 1999 and involved in IT support since 1985, Diane is the author of several books and video training CDs and online training classes for Microsoft Outlook. You can find her helping people online in Outlook Forums as well as in the Microsoft Answers and TechNet forums.