On export, you may receive this error:

This was determined to be caused by items in the AP_Invoice table having a null in their Due_Date.
Run:
Select * from AP_Invoice where Due_Date is null
That should reveal the records with a null value. Then run:
Update AP_Invoice
Set Due_Date = ‘Whateverdate is correct’
Where Invoice_Id = ReplaceWithID
That should correct the null value and allow the report to export correctly.