The issue being discussed in this article is:
You get this error when generating a Custom Legacy SI5 Report:
This custom report or any of its sub report used 'PhaseItems' as a report data source pattern which is deprecated. To learn more how you can solve this problem click Yes.
The following is the screenshot of the error:
The following is the cause:
You are attempting to run an SI5 Report that has been imported into SI 2015 and later versions.
The following is the resolution:
Open Report Settings from the Control Panel or from the Reports tab in the Project Explorer or Project Editor interfaces and change the Populate phase items setting to "Yes."
Enabling this setting can result in some lag time when running these reports.
If you cannot resolve this issue, please open a Support Ticket.