Field codes link to content inside or outside of documents (e.g. a table of contents). When this content is moved you’ll get a “Error! Reference not found.”, which at this point if you are not the author of the document makes it impossible to guess what the text may have said before. This is why it is advisable to remove field codes entirely before you distribute a final document to make sure important information is not lost.
The fastest way to do this is to select all text with CTRL + A and then press CTRL + SHIFT + F9 to remove all field codes. To remove field codes located in headers and footers (e.g. page numbers) you will have to click these separately and repeat the procedure.
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