Microsoft Windows Error Code 0xC0000900: How to Fix It
Medium 20-40 minutes Medium Severity
Verified June 2026
- Error Code
- 0xC0000900
- Brand
- Microsoft Windows
- Product Type
- operating_system
- Severity
- Medium
- DIY Difficulty
- Medium
- Estimated Fix Time
- 20-40 minutes
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Tools You'll Need
- Active Directory administrative tools
- Event Viewer
- ADSI Edit
- Administrator account
How to Fix Error Code 0xC0000900
-
Identify the Affected Object
Ensure you have administrative privileges to view event logs. -
Verify Display Name in Active Directory
Be careful not to modify other attributes accidentally. -
Correct the Display Name
-
Force Replication
Replication may take a few minutes; monitor event logs for success. -
Trigger a Full Sync of the Affected Object
Run these commands as Administrator. -
Verify Resolution
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When to Call a Professional
If the error persists after correcting the display name and forcing replication, you may have deeper Active Directory database corruption. Contact a Microsoft support professional or Active Directory consultant.Frequently Asked Questions
What causes Windows error 0xC0000900?
This error is caused by an invalid LDAP display name in Active Directory, usually due to a malformed 'displayName' attribute on a user, group, or other object. It can also occur from directory replication issues.
Can I fix error 0xC0000900 without ADSI Edit?
Yes, you can use PowerShell to modify the displayName attribute. Use Set-ADUser or Set-ADObject cmdlets to correct the value. For example: Get-ADUser 'username' | Set-ADUser -DisplayName 'Correct Name'.
Will rebooting the server fix error 0xC0000900?
Rebooting may temporarily clear the error if caused by a replication backlog, but it will return unless the underlying object attribute is corrected. Always fix the displayName attribute first.
Is error 0xC0000900 harmful?
It can prevent applications from authenticating against Active Directory or cause incomplete user/group lookups. While not a system crash, it disrupts directory services and should be resolved promptly.
How do I prevent error 0xC0000900 from recurring?
Ensure that any script or process creating or modifying Active Directory objects validates the displayName attribute for proper formatting. Also, monitor replication health regularly.