When upgrading to 18.4 you may encounter this error while running the 18.4 Configuration Center
"ERROR: Upgrading Server installation error: Migration Task 'Undefine ToDo Attributes' encountered an error performing the migration.
Failed to undefine attribute Work To Do. Error: Undefine attribute Work To Do failed; AttributeStillInUse."
In 18.4 there is a migration task that is migrating certificate objects with "work to do". In some rare cases, there might be an object such as an application, that has this attribute as well. If this is the case, you will need to remove the "work to do" attribute and re-run the Venafi Configuration Center.
You can use the following SQL query to find out which objects have a "work to do" attribute written.
Select * from config_objects where GUID in (select GUID from config_contains where attribute='Work To Do')
If you are unable to remove the attributes on your own, or with the help of a DBA, please contact support.