Updating Excel Links during an ACTIVE Powerpoint Presentation

[mikeb7500]

In an ACTIVE Powerpoint presentation, I've added a button to open an Excel Spreadsheet to add information. I can then enter the info into the Excel Spreadsheet, received from the client, but it won't automatically update the links back into the presentation. How can I get the links to automatically update back in the same Powerpoint prentation? Thanks in advance.