Problem
An Error pops up when editing a workflow schedule:
Object of type 'Newtonsoft.Json.Linq.JArray' cannot be converted to type 'SourceCode.SmartObjects.Service.K2Management.EventBus.Scheduler.ProcessScheduleInfo[].'There is no issue when creating a new one from K2 Management
Solution
On the K2 server and on the web server where the K2 site is hosted, change the Long and Short Date Formats to MM/dd/yyyy.