Sometimes this occasionally pops up when opening Excel and a user may click "Yes" on it. If that is the case, follow this tutorial

1. Open Excel and go to "File" -> "Options"
2. On the Excel Options window, go to "Add-ins" -> "Excel Add-ins" -> "Go..."
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3. Click the checkbox for Ssserver (if this is not appearing, click "Browse)
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4. Point to this location: C:\Program Files\insightsoftware\Spreadsheet Server Suite\_Common\SSServer.xll (it could also be Program Files (x86))
5. After pointing to that location, the add-in show appear on the list, click the checkbox next to it then click "Ok"
   1. If you are unable to find the add-in, there is a possibility that it is not installed on the machine. If that is the case, please contact help desk to install the program