The CDXZipStream add-in provides custom zip code and other formula in Excel. The add-in must be installed for these functions to calculate correctly. Uninstalling the add-in will cause a #NAME? error to appear in the cell indicating that Excel does not know what to do with the formula.
If you email or send a worksheet to someone else who does have CDXZipStream installed the same error will occur whenever Excel recalculates. Excel will recalculate under many situations you might not expect such as opening the spreadsheet, moving rows or closing the spreadsheet down. Even though the formulas calculated and displayed correctly on your computer the #NAME? error can easily appear on another without CDXZipStream installed.
There are two ways to handle this situation when emailing reports. The first is to set the spreadsheet recalculation to manual using the Excel - Formulas - Calculation Options menu option. The second is to set all of your formulas to values using the Excel Copy and Excel Paster special options. Using either of these options will insure that your intended recipient will be able to see the results you expected.