Description of Error:
When attempting to create an invoice associated with a dispatch the following error appears:
Conversion from type 'DBNull' to type 'Date' is not valid.
This error can also occur after upgrading ESC to a newer version if there are any dispatches that have been completed without a date in the date off field.
Cause of Error:
The dispatch that is being associated with the invoice does not have a valid Dispatch Date or Date Off.
Recall the dispatch you are attempting to invoice on the Dispatch Entry screen. Look for line items on the Schedule tab of the associated dispatch that have a Disp Time or Time On value but nothing in the Dispatch Date field or a time in the Time Off field but nothing in the Date Off field. Enter a valid date in those fields and save the dispatch. After doing this you should be able to create the invoice without any errors.
If a date does appear in those fields, it is possible that it is not formatted using the standard US format of mM/dD/YYYY. If that appears to be the case, please see this article for full details on how to fix it.