Can't delete a CMDB CI record: Delete of XXX not allowed because of a reference in record XXX within the Configuration Item fileIssue When trying to delete a CI from the CMDB, you get this error Delete of XXX not allowed because of a reference in record XXX within the Configuration Item file ReleaseNew York or later only.CauseThe Duplicate Of field was added to the Configuration Item table in the New York release, as a replacement for re-using the Discovery Source field for marking CIs as duplicate. See the release note. The Cascade Delete rule for this new field is "Restrict", meaning if anything references the record you are trying to delete from this field in another record, then you can't delete. If this CI has been deemed the main CI of a set of Duplicates by the Identification & Reconciliation engine or the CMDB Health jobs, then there will be at least one other CI referencing the record you want to delete using this field. And that's why the delete is restricted and you see the error.ResolutionTo have this error means this CI has been detected as part of a set of duplicate CI, and so there will be a De-Duplication Task for this set of duplicates. See the documentation for the correct way to resolve duplicate CIs. Instead of manually deleting the CI, the Duplicate CI Remediator will do the delete, but will do this is a much safer way that preserves/merges most of the values and relationships with other CIs, assets and tasks as possible. For example, Incidents linked to any of the CIs in the set will now point to the CI you decided to keep, and will not end up orphaned. To find which De-Duplication Task is involved: Copy the sys_id of the CI. Right click the header of the CI form, and select "Copy sys_id"Open a list of the Duplicate Audit Results tablehttps://<instance name>.service-now.com/duplicate_audit_result_list.doAdd a filter, and run:"Duplicate CI" IS <paste the sys_id>Click on the DUPxxx link in the Follow-On Task column, to open the De-Duplication TaskOn the De-Duplication Task form, click the Remediate button If a huge number of records are involved, then it will probably be necessary to run a custom script to clear out the 'Duplicate of' fields of any CIs that reference the CIs you plan to delete. That will avoid the error stopping the deletes. A second script could then be used to do the delete.Related LinksKB0816113 Where did the "Unknown" CI in the CMDB come from, and why?