SPIncomingEmailService.RetryDeliveryInterval property

Gets or sets the maximum duration, in hours, that undelivered messages remain in the drop folder before being deleted.

Namespace:  Microsoft.SharePoint.Administration
Assembly:  Microsoft.SharePoint (in Microsoft.SharePoint.dll)

public int RetryDeliveryInterval { get; set; }

Property value

Type: System.Int32
The maximum duration, in hours.

The default value for this property is 24 hours, or one day.