# Review Synchronizing Between AD DS and AD LDS Enters Endless Loop if the base DN is a Grandchild OU before AD/DNS changes > Use Synchronizing Between AD DS and AD LDS Enters Endless Loop if the base DN is a Grandchild OU to review this narrow operational decision without extending the source beyond its stated scope. - Canonical URL: https://update.dsesecurity.com/updates/review-synchronizing-between-ad-ds-and-ad-lds-enters-endless-loop-if-the-base-dn-is-a-grandchild-ou/ - Publisher: Detection Systems & Engineering (DSE Security) - Author: DSE Security Editorial Team - Published: 2026-08-27T17:00:26+00:00 - Modified: 2026-08-27T17:37:18+00:00 - Last reviewed by DSE: 2026-08-27 - Resource type: Playbook - DSE priority: Advisory - Topics: Cybersecurity, Microsoft 365 & Identity, Networks & Infrastructure - Reading time: 3 minutes ## What you need to know Use Synchronizing Between AD DS and AD LDS Enters Endless Loop if the base DN is a Grandchild OU to review this narrow operational decision without extending the source beyond its stated scope. ## Potentially affected Teams, systems, services, or facilities within the stated scope of Synchronizing Between AD DS and AD LDS Enters Endless Loop if the base DN is a Grandchild OU ## DSE recommendation Compare the observed state with the cited official source, document applicability and exceptions, and test any approved change with rollback safeguards. ## Article Keep this document to one review outcome: Review Synchronizing Between AD DS and AD LDS Enters Endless Loop if the base DN is a Grandchild OU before AD/DNS changes. Only the official source and traced locations below supply facts. Confirm applicability before acting. ## Source fact: The official [Synchronizing Between AD DS and AD LDS Enters Endless Loop if the base DN is a Grandchild OU](https://learn.microsoft.com/en-us/troubleshoot/windows-server/active-directory/adamsync-cant-sync-basedn-grandchild-ou) from Microsoft supports the following bounded statements: - At Summary, Microsoft states: “This issue occurs when you specify a grandchild organizational unit (OU) as the base distinguished name (base DN) in the Adamsync configuration file.” The research record locates this support at Summary. - At Summary, Microsoft states: “This article describes the symptoms, cause, and workarounds for this known issue in the Adamsync tool.” The research record locates this support at Summary. The source support ends with the statements listed above. Use them to examine Active Directory objects, search bases, domain controllers, delegated roles, cmdlet parameters, and the DNS paths used to locate directory services in the applicable environment, not to imply a wider guarantee. ## What the source does not establish The cited page and retained statements do not establish the current state of any DSE or customer environment, prove that the documented configuration is applicable, or authorize a production change. Confirm supported versions, dependencies, and the current live source before use. No current deployment state or change approval follows from the source alone. Validate Active Directory replication, Windows DNS, domain-controller location, time, network reachability, privileges, and protected credentials, and treat examples or options as conditional inputs rather than defaults. ## Applicability questions - For source statement 1 at Summary, which observable configuration, record, or test can confirm applicability here? - For source statement 2 at Summary, which observable configuration, record, or test can confirm applicability here? - Which owner can attest to the recorded state of Active Directory objects, search bases, domain controllers, delegated roles, cmdlet parameters, and the DNS paths used to locate directory services, including exceptions? - What baseline for Active Directory replication, Windows DNS, domain-controller location, time, network reachability, privileges, and protected credentials must accompany the source-specific observation? - Which success, stop, and escalation criteria are written before testing begins? ## DSE recommendation: DSE recommends using the cited source as the evidence anchor for this decision. Make the source, asset scope, owner, and expected outcome explicit in the review record. Record the source location, examined part of Active Directory objects, search bases, domain controllers, delegated roles, cmdlet parameters, and the DNS paths used to locate directory services, observed and expected states, owner, and reason for deviation. Do not move from citation to production in one step. Pilot the decision where practical, observe agreed signals, retain a reversal point, and verify Active Directory replication, Windows DNS, domain-controller location, time, network reachability, privileges, and protected credentials. Handle credentials, keys, recovery data, and personal information through approved secure channels. ## Verification and evidence Build a reproducible chain from Summary; Summary to the observed environment. Useful domain evidence includes sanitized command transcripts, parameter records, directory exports, authorization records, DNS locator tests, and before-and-after state; label every item with scope, timestamp, collector, and stable identifier. Label this evidence set DSE-20260827-420 so observations, approvals, exceptions, and later rechecks cannot be substituted from another source review. Retain the starting state, authorization, execution record, outcome, deviation, and final state as one review package. Move disruptive checks to an approved test path. Reopen the decision when versions, design, dependencies, ownership, or official guidance changes. ## Official references - [Synchronizing Between AD DS and AD LDS Enters Endless Loop if the base DN is a Grandchild OU](https://learn.microsoft.com/en-us/troubleshoot/windows-server/active-directory/adamsync-cant-sync-basedn-grandchild-ou) — Microsoft ## Primary reference - Name: Synchronizing Between AD DS and AD LDS Enters Endless Loop if the base DN is a Grandchild OU - Authority: Microsoft Learn - URL: https://learn.microsoft.com/en-us/troubleshoot/windows-server/active-directory/adamsync-cant-sync-basedn-grandchild-ou - Source publication date: Not stated by the source ## Citation and use Preferred citation: “Review Synchronizing Between AD DS and AD LDS Enters Endless Loop if the base DN is a Grandchild OU before AD/DNS changes,” DSE Security, https://update.dsesecurity.com/updates/review-synchronizing-between-ad-ds-and-ad-lds-enters-endless-loop-if-the-base-dn-is-a-grandchild-ou/ Publishing principles: https://update.dsesecurity.com/updates/dse-updates-editorial-methodology/ Usage and citation policy: https://update.dsesecurity.com/usage/ Copyright © 2026 Detection Systems & Engineering. 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