Every once in a while I come across a problem where I open an Excel document and am notified of external references, even though I’m certain the document doesn’t or shouldn’t contain any external references. A common message is:
This workbook contains links to one or more external sources that could be unsafe
In order to find these references in Excel 2016, click the “Data” tab at the top. Then, under the “Queries and Connections” section, choose “Edit Links.” From there, a dialog will pop up showing any links and allowing you to check the status of the links. If the links are truly broken, checking the status should confirm that.
To break the connection, you can simply choose “break” with the appropriate connection selected. Any cell where a value was dependent on the connection was be converted to the current value, so you shouldn’t lose data by breaking the connection – it will simply no longer update along with the connected data source.