The error seen when working with The Financial Edge API is a type of warning that can be suppressed using the IBBWarningRule interface:
Public Sub CreateAPInvoice()

   Dim oInvoice As CAPInvoice
   Set oInvoice = New CAPInvoice
   With oInvoice
       .Init fe_application.SessionContext
       .Fields(APINVOICES_fld_AP7VENDORSID) = 2
       .Fields(APINVOICES_fld_REMITTO) = 1
       .Fields(APINVOICES_fld_POSTDATE) = Date
       .Fields(APINVOICES_fld_DESCRIPTION) = "NEW Test APInvoice"
       .Fields(APINVOICES_fld_PAYMENTMETHOD) = "Check"
       .Fields(APINVOICES_fld_INVOICEAMOUNT) = "$12.12"
       .Fields(APINVOICES_fld_INVOICEDATE) = "06/23/2017"
       .Fields(APINVOICES_fld_INVOICENUMBER) = "2032"
       With .Distribution.Add
          .Fields(BBDISTRIBUTIONS_fld_DEBITACCTNUM) = "01-2030-00"
          .Fields(BBDISTRIBUTIONS_fld_CREDITACCTNUM) = "01-2020-00"
          .Fields(BBDISTRIBUTIONS_fld_AMOUNT) = "10.00"
          .Fields(32) = "API Description"
          .Fields(BBDISTRIBUTIONS_fld_PERCENT) = 100
       End With

       .ApplyVendorDefaults False
        Dim oIBBWarningRule As IBBWarningRule
        Set oIBBWarningRule = oInvoice
        '' Suppress all warnings: oIBBWarningRule.OverrideAllWarnings = True '
        '' 1 = There are open Purchase Orders for this Vendor.
        '' 2 = There are unapplied credit memos for this vendor.
        '' 3 = This invoice may cause you to exceed the current credit limit of $0.00 for this vendor.
        oIBBWarningRule.OverrideWarning(1) = True

   End With

   Set oInvoice = Nothing
End Sub

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