When you open templates or files using a hyperlink button or from Outlook's Shortcut navigation pane, you'll receive an unsafe hyperlink warning. You can disable the warning by editing the registry.

You may also receive the file open or save dialog when using a hyperlink button or shortcut. To disable this dialog when the "Always ask" field is grayed out, run Outlook as administrator. The "always ask" checkbox should be clickable. If not, you'll need to edit the registry for each file type. See Disable "Always ask before opening" dialog for more information.

The solution

The solution applies to all Office applications, not just Outlook.

Add a registry value to disable the warning dialog.

Open the registry editor and browse to the following registry subkey for

Office / Outlook 2016:

HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Common\Security
DWORD: DisableHyperlinkWarning
Value: 1 (disable the warning), 0 (enable the warning)

Office / Outlook 2013:

HKEY_CURRENT_USER\Software\Microsoft\Office\15.0\Common\Security
DWORD: DisableHyperlinkWarning
Value: 1 (disable the warning), 0 (enable the warning)

Office / Outlook 2010:

HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Common\Security
DWORD: DisableHyperlinkWarning
Value: 1 (disable the warning), 0 (enable the warning)

Office / Outlook 2007:

HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Common\Security
DWORD: DisableHyperlinkWarning
Value: 1 (disable the warning), 0 (enable the warning)

Note: If the Security key does not exist in your registry, you'll need to create it too.

Right click on Security key and choose New, DWORD.
Type (or paste) DisableHyperlinkWarning as the Value name then double click on it.
Enter 1 as the Value data to disable the warning. Delete the key or use a value of 0 to enable the warning.

Do It For Me

If you don't want to edit the registry yourself, you can download and run the following registry key for your version of Outlook. These files set the key in the User path.

Outlook 2016 and newer Outlook 2013 Outlook 2010 Outlook 2007

Group Policies Registry Edit

Administrators will add the DisableHyperlinkWarning DWORD to the Policies key instead:

Outlook 2016:

HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\16.0\Common\Security
DWORD: DisableHyperlinkWarning
Value: 1 (disable the warning), 0 (enable the warning)

Outlook 2013:

HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\15.0\Common\Security
DWORD: DisableHyperlinkWarning
Value: 1 (disable the warning), 0 (enable the warning)

Outlook 2010:

HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\14.0\Common\Security

Outlook 2007:

HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\12.0\Common\Security

Do It For Me

If you don't want to edit the registry yourself, you can download and run the following registry key for your version of Outlook. These files update the Policies path.

Outlook 2016 (Policies path) Outlook 2013 (Policies path)
Outlook 2010 (Policies path) Outlook 2007 (Policies path)