IT Error Decoder
Entra ID

How to Fix Entra ID directory sync error: Object not synced

Last reviewed

Error message

On-premises object failed to sync to Microsoft Entra ID — Entra Connect reports export failure.

Sync failures are almost always object-level. Identifying which object failed is half the work.

What this error means

Entra Connect couldn't push (export) an object from on-prem AD to Entra ID. The object stays out of sync until the underlying issue is fixed.

Why this happens

Common causes: duplicate proxy address, attribute too long, invalid character in UPN, schema mismatch, or filtering rules excluding the object.

Quick fix (for end users)

  • Open Entra Connect Health and find the failing object.
  • Note the exact attribute the error names.

Admin / engineer fix

  • On the Entra Connect server, run a sync and check for export errors.

    command
    Start-ADSyncSyncCycle -PolicyType Delta

  • Look at the error in the Synchronization Service Manager — it names the failing attribute.

    command
    miisclient.exe

  • Fix the attribute on-prem (e.g. remove duplicate proxyAddress, trim long values, escape invalid characters in UPN).

Step-by-step fix

  1. Identify the failing object via Entra Connect Health or Synchronization Service Manager.

  2. Read the specific attribute error.

  3. Correct the attribute on-prem; the next sync clears the error.

Affected products

Microsoft Entra Connect · Microsoft Entra ID

Common variations of this error

People also see these phrasings of the same problem:

  • Entra Connect export error
  • Azure AD Connect sync failure

Still broken? Try these

  • Some attributes (e.g. immutableId) require a `dirsync soft-match` operation to repair.
  • Use IdFix to scan for known-bad values across your AD.

Related errors

Related searches

  • entra connect sync errors
  • fix azure ad connect export

Frequently asked questions

What does "Entra ID directory sync error: Object not synced" mean?

Entra Connect couldn't push (export) an object from on-prem AD to Entra ID. The object stays out of sync until the underlying issue is fixed.

What causes "Entra ID directory sync error: Object not synced"?

Common causes: duplicate proxy address, attribute too long, invalid character in UPN, schema mismatch, or filtering rules excluding the object.

How do I fix "Entra ID directory sync error: Object not synced"?

1. Identify the failing object via Entra Connect Health or Synchronization Service Manager. 2. Read the specific attribute error. 3. Correct the attribute on-prem; the next sync clears the error. Always test changes in a non-production environment first.

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