You may need to delete this directly from the database:
- Stop the Orion services
- Log on to the Solarwinds DB
- Delete the rules from the table UDT_Rule
delete from UDT_Rule where Name = 'Rule Name'
For example: delete from UDT_Rule where Name = 'Whitelist'
4. Restart the Orion services
5. Open the Web console and try creating the white list rule again.