If this is version 8 of MasterMine, the most likely issue is a conflict with a COM add-in in Excel called FoxItReader.
In Excel (depending on the version) turn off the COM add-in by clicking "File", "Options", "Add-Ins" on the left side.
In the Excel Options dialog, at the bottom next to "Manage:", select COM Add-ins and click "Go...". Uncheck the "Foxit Reader PDF Creator" item, then click "OK".
This temporarily disables the FoxitReader in Excel. If you need to have this function available, you can turn it on again by reversing these steps, after closing your MasterMine report.