Links are Prefixed with BLOCKED::

Last reviewed on September 19, 2012

When you receive an HTML message, links in it may not work or the File, Open dialog will open, asking to associate an executable file with the link.

Looking at the source, you’ll see the URL is prefixed with BLOCKED::, like this:

<A title=http://office.microsoft.com/ href="BLOCKED::http://office.microsoft.com/">Office Online</a>

This is a security feature in Outlook and may happen when URLs are copied from one email message and pasted into another message.

You may be able to control it by adjusting the blocked external context setting in Outlook 2003. You’ll find these settings on the Tools, Options, Security, Change Automatic Download Settings menu or click on the Infobar of a message containing blocked content and choose Change Automatic Download Settings.

Note that this is NOT a common problem and we are not sure why its a problem for some people and others have never seen it. Internet security settings may be a factor. You may only see it if you don't have anti-virus software installed.

Workarounds

Internet Zone Security settings

  • Opening the message in the Internet zone (View menu) may allow the links to work.
  • Delete blocked:: from the beginning of the URL in the address bar.
  • In Outlook 2002/2003: set Outlook to use the Internet Zone. This is on the Tools, Options, Security tab.

Note: We do not recommend lowering the internet Security settings or Setting Outlook to use a less restrictive Internet Zone. Resetting the Internet Zone to use the default settings may help.

Warning: Using any zone other than Restricted will lower your security and could leave you open to possible infection from Java exploits. See Why you should block external content in Outlook by default for more information.

Notes

In Outlook 2003, the screentip will include the URL and title (if present):
Blocked URL
The URL may still work correctly in both Internet Explorer and Firefox.

In Outlook 2002, you’ll see just the title field, if present, in the screentip:
Blocked URL Outlook 2002
The File, Open dialog opens for you to choose an exe to associate with it. After associating Internet Explorer, the address bar will show blocked:
blocked url in address bar

Written by

Diane Poremsky
A Microsoft Outlook Most Valuable Professional (MVP) since 1999, Diane is the author of several books, including Outlook 2013 Absolute Beginners Book. She also created 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.

If the Post Coment button disappears, press your Tab key.