When working in Service Desk users may come across the error:
Error: Item has already been added. Key in dictionary: 'xxx' Key being added: 'xxx'
where xxx can be a number or a String.
In earlier versions on Service Desk this usually occured when trying to open a form window and xxx was numerical. The cause was that the tabs or collections had not had their tabbing order properly set.
This problem can also occur when a particular users' own information relating to their personal settings has become corrupted. In this case xxx is a String 'ActionPanelConfig'. The way to fix this is to remove the users' settings from the database, the script below will achieve this, you should replace SA with the name of the affected User.
DELETE FROM tps_application_user_setting
WHERE tps_user_guid = (SELECT tps_guid FROM tps_user WHERE tps_name = 'SA')
As with all scripts do not run this without first taking a full, restorable backup of the database first. Furthermore, where possible, test this script on a test system before applying to your live environment.