I've instaled Milestones PM - Project Management however when I click on Initialize the app I get the following error:
Insert failed. First exception on row 0; first error: CANNOT_INSERT_UPDATE_ACTIVATE_ENTITY, Milestone1_Task_Trigger: execution of AfterInsert caused by: System.DmlException: Insert failed. First exception on row 0; first error: LIMIT_EXCEEDED, Maximum per user subscription limit reached.:  Class.Milestone1_Task_Trigger_Utility.handleTaskAfterTrigger: line 65, column 9 Trigger.Milestone1_Task_Trigger: line 8, column 3: 
An unexpected error has occurred. Your development organization has been notified.
Can anyone help?