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‘This document contains links that may refer to other files’ – How To Handle

Posted by Jamie on January 25, 2019

If you’re trying to open or copy a Microsoft Office document but keep seeing ‘This document contains links that may refer to other files’, it can be incredibly frustrating. The alert stops you doing anything with the document and you cannot open or copy it until you disable the link or work around the alert. Fortunately you can do both, here is what you need to do when you see ‘This document contains links that may refer to other files’ in Microsoft Office.

While the alert can be annoying, it is there for our protection. It is there because of Microsoft’s Dynamic Data Exchange (DDE) protocol. This enables data sharing between documents to help with version control, collaboration and other productivity features. It can also be used to spread malware and has been attributed to some serious attacks in the past.

Microsoft knows this and added a security check to try to prevent these attacks from happening.

This document contains links that may refer to other files

It is possible to work around this alert but you need to be careful if you do that. You need to make sure you are confident of the sender and of the legitimacy of the document in question and any links it may contain. Even internal documents can be infected so perform your due diligence before using these methods.

Remove links from Word or Excel

You can remove links from Word or Excel documents to stop this message. This will obviously remove any links to other documents but you can always type a document URL manually without creating a hyperlink.

  1. Open Word or Excel and select File from the menu.
  2. Select Options and the Quick Access Toolbar from the left menu.
  3. Add Edit Links to Files to the toolbar.
  4. Select the Edit Links shortcut in the toolbar at the top of the document.
  5. Select the file in question and then select Break Link.
  6. Select OK to save changes.

You should now be able to copy or use the file as necessary.

You can also tell Word or Excel to update links dynamically although you need to be sure of the security of your documents.

  1. Open Word or Excel and select File from the menu.
  2. Select Options and Advanced in the new window.
  3. Scroll to the General section and check the box next to ‘Prompt to update automatic links at open’.
  4. Select OK to save the change.

You can also uncheck the box if you change your mind and would prefer not to dynamically update them.

If you still see the error after these changes, make sure to disable the same options under Printing Options.

  1. Open Word or Excel and select File from the menu.
  2. Select Options and Display from the left menu.
  3. Check or uncheck the box by ‘Update linked data before printing’ under Printing Options.

This setting under Printing Options is the one often missed. While it should logically only be relevant when selecting to print a document, it can trigger the ‘This document contains links that may refer to other files’ alert elsewhere too. If you have modified the main settings, changing this print setting should see the end of the error.

If you find these alerts annoying enough, you can disable DDE through a registry change. It was highlighted in that Technet page linked above from Microsoft and works like a charm. It does mean you will never be able to link between documents but doesn’t stop you adding link addresses within the document.

  1. Open the Windows registry with ‘regedit’.
  2. Navigate to ‘HKEY_CURRENT_USER\Software\Microsoft\Office\<version>\Word\Options\WordMail.
  3. Change the key DontUpdateLinks(DWORD) to 1.

If the key is not present, create it using the same settings. Right click an empty space in the right pane of WordMail, create a New, DWORD and give it a value of 1. If you don’t like the change, you can safely delete this registry key.

DDE attacks

I mentioned earlier that the alert stems from DDE attacks. These attacks use malware that utilize Microsoft’s Dynamic Data Exchange to spread. The malware can be included in infected document links, email attachments, Excel spreadsheets and all manner or links.

These attacks were discovered a couple of years ago and were initially through infected Excel links. This post over at SensePost explains a lot about how DDE attacks work and why they needed protecting against.

Dynamic linking between documents is a valuable tool for sharing data. It’s a real shame it has bee hijacked as an attack vector but it is what it is. If you now see ‘This document contains links that may refer to other files’ in Microsoft Office, you know what to do.

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