# Deduplication of User Accounts in ContactManager
Deduplication in ContactManager is used to merge duplicate user accounts into a single master account, ensuring consistency across all linked relations, matters, and references.
# Requirements
ContactManager version 26.2 (26-03-2026) or newer
# When to Use Deduplication
Use the deduplication function when:
- A user has multiple accounts (e.g., test accounts, renamed accounts).
- Migrated or imported data has created duplicate user entries.
- You want to consolidate activity history, ownership, or references under one single user.
When an admin performs a deduplication, the duplicate account is automatically deleted after merging its references.
# Accessing the Deduplication Function
Navigate to Users in the ContactManager configuration area. Select the user you want to keep as the Master User. Click on the Deduplication button in the toolbar:
Deduplication Dialog Overview After selecting the master account, a dialog appears where you can choose the account to merge into it:
Fields in the Dialog
- Master CmsUser: The account that will remain after merging.
- Duplicate CmsUser: The account whose references will be transferred and which will be deleted.
Click De duplicate to confirm the merge.
# What Happens During Deduplication?
When the deduplication process runs: All references to the duplicate user are updated This includes (but is not limited to):
- ModifiedBy fields
- CreatedBy fields
- Ownership references
- Activity references
- Linked relations or contact records
This behavior is confirmed in the ContactManager log.
The duplicate account is deleted
Only administrators can perform this action. The duplicate user will be removed after references are transferred.
# Best Practices
Always verify the correct master account before deduplication. Check email addresses Communicate with end users before removing old accounts, especially if login methods or linked systems (e.g., MailChimp, Outlook) depend on them