This can occur based on the Calendar format setting in place on the Windows workstation.

To resolve this in Windows 7 or higher:
  1. Go to Windows > Control Panel > Date and Time > Change Date and time > Change Calendar settings. 
  2. Under Calendar, move the range for two-digit years up to a date range that will include all Class Years in the Raiser's Edge database. 
User-added image

NOTE: If Blackbaud Hosts your database, you will need Regional Settings added to the Blackbaud Hosting Services portal so the change can be made. This setting needs to be made for each user prior to accessing The Raiser's Edge.