Custom XML Data

The problem here is that Microsoft has apparently used the term "custom XML" for two different things.

If a document created by a very early copy of Word 2007 from before the lawsuit was decided is opened in any later copy of Word, and it contains the "bad" custom XML (that is, patent-infringing, not dangerous to you), that stuff will automatically be removed. You don't have any choice in the matter, but you also don't have to run the Document Inspector to find out about it.

Later versions of Word may place certain information into "good" custom XML. The only thing I've ever seen there is information about bibliography references and styles (for example, whether the document uses APA 6th edition or Chicago style, etc.). Not only is that stuff harmless when it's there, it might be a problem if you remove it and lose the information it contains.

If you want to take a look at it before (or instead of) deleting it, here's how:

• In Windows Explorer, go to the folder containing the document file.
• Make a copy of the file (the quick way is to hold down Ctrl while dragging the file's icon and dropping it on a blank space in the file list).
• With the copy selected, press F2 or right-click and choose Rename. Change the file's extension to .zip and press Enter.
• Double-click the zip file to open it like a folder.
• Double-click the subfolder named customXml.
• Double-click each of the files (with extension .xml) in the subfolder. They'll open in whatever program you have assigned to open text files, probably Notepad.

A lot of what you see will be XML tags within brackets like < > and what look like Internet addresses (although they don't usually correspond to real web pages). Some of it will be recognizable. Here's a sample:

<b:Sources SelectedStyle="\APASixthEditionOfficeOnline.xsl" StyleName="APA" Version="6" xmlns:b="http://schemas.openxmlformats.org/officeDocument/2006/bibliography" xmlns="http://schemas.openxmlformats.org/officeDocument/2006/bibliography"></b:Sources>

When you're satisfied, close the XML files and delete the zip file.

One other thing that may make you more at ease: I've never heard of malware of any kind that could be transported in a document's custom XML. The worst risk it poses is that it might contain some personal information that you don't want to share with anyone else.

In addition to the things that Jay has mentioned, 3 other things will result in your document having Custom XML Data. Two of them may be becoming more widespread as more people use "the cloud" to store documents. However, I do not think you need to be too concerned about them, as explained below.

 a. if the document you are working on was created on, has been opened from, or ever passed through, a SharePoint site, it wil probably have custom XML containing "SharePoint properties"

 b. if the document you are working on was created on, has been opened from, or ever passed through, a Business OneDrive site, it wil probably have custom XML containing "properties"

 c. If anyone has ever added one or more of a particular set of document properties, Word will create a custom XML part to contain their values. These are the "Cover Page Properties", which in the English language version of Word are called "Abstract", "Company Address", "Company E-mail", "Company Fax" and "Company Phone". You would typically insert them from Insert->Quick Parts->Document Property...

However,

The "ordinary" personal version of OneDrive (formerly "SkyDrive") does not create Custom XML, unlike the OneDrive for Business version.

Word's document inspector does not detect the "Cover Page Properties" - presumably because they are known to Word and regarded as being like any other property.

Even the SharePoint and OneDrive custom XML parts are primarily there to allow users to insert additional "document property information", over and above the standard built-in properties such as Author, Title and so on. The mechanism Word provides to let users do that is "content controls". Even if you have inserted those property values using content controls, as far as I know if you remove the custom XML, all that will happen is that changes to one content control will not result in changes to any others: whatever property values last appeared in the document should remain unchanged.

[Post from user TT.thomastan has been split off to this new thread.]

Thank you so much, Jay!