Deduping

Remove duplicate records from the campaign worksheet. Click on the Deduping box under Advanced Options for the Deduping tab to appear.

REMEMBER: Last in first off!

Add a dedupe rule name and select the field to match the duplicate records on.

The rules can be applied to all segments, several segments, or separate rules can be created for each of the segments.
To create separate dedupe rules:

Click on the New Dedupe Rule
Enter a name in the Rule Name field
Select the Segment the rule is to apply to
Close the Segment window
Choose the dedupe rules by selecting from the fields under Dedupe records using the fields selected below.

Select the field(s) duplicate records in the worksheet will match against, eg, email.

Multiple dedupe rules can be used.

Create the dedupe rules in order of priority

When using multiple dedupe rules the rules are processed one at a time. The first rule will process the worksheet removing any records that match on the selected field(s) in the rule. The second rule will be process the worksheet on completion of rule one — and so on.