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Use the Edit Citation tool to add page numbers into citations.
If 
If you have “Cite While You Write” turned off, you must first format the citations before you use Edit Citation to add page numbers by clicking the “Update Citations and Bibliography” button in Word’s EndNote ribbonThis process works for both in-text and footnotes styles – provided the Cited Pages field is listed in the citation/footnote template of the output style being used, which is normally the case
Adding page numbers to citations
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Click the OK button to save the changes you have made and then reformat the document
This process works for both in-text and footnotes styles – provided the Cited Pages field is listed in the citation/footnote template of the output style being used, which is normally the case
Unformatted Citations (Cite While You Write turned off)
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The page numbers will appear when you click the “Update Citations and Bibliography” button in Word's EndNote ribbon.
This This works for both in-text and footnotes styles – provided the Cited Pages field is listed in the citation/footnote template of the output style being used, which is normally the case