This error can occur when the Start_Date_Benefit on the benefit indicated in the error is null.  Resolve the error by zooming <F10> on the benefit(s) attached to the batch item and adding the start date where appropriate.  Posting should then succeed.

This can also happen on pledge payments (PPs) of a sustaining gift (SG) pledge if the Schedule_Start_Date or the Payments_In_Schedule on the pledge (PL) is null.  To resolve this situation, adjust the original pledge to include the Schedule_Start_Date and/or Payments_In_Schedule value(s).

If the error persists after taking the actions indicated, or if you have questions, please create a support request at providing the details of the issue and referencing this solution.