To delete a resource in MultiCalendar C/S Edition, you need to make sure the current login account have the permission to delete that resource. To do so, go to Start Button -> Programs -> MultiCalendarCS3.0 -> User Management Tools. The default admin account for User Management Tools is as following: user: Admin password: changeme In the User Management Tools, make sure the user account which will be used to delete that resource have the "Able to Delete" checked. For example, if you will use "testuser" account to login MultiCalendar and delete the resource named "Untitled Resource 1", you should set the following permissions on testuser account: