Find the links for the message "This workbook contains links to other data sources."

I get the following message when I open my workbook.

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Microsoft Excel

This workbook contains links to other data sources.

*If you update the links, Excel will attempt to retrieve the latest data.
*If you don't update the links, Excel will use previous information.

Note that data links can be used to access and share confidential information without your permission and possibly perform other harmful actions. Do not update the links if you do no trust the source of this workbook.
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I took out all external links but am still getting the message. Is there an easy way to see what I am missing?