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schema mismatch
About this tag
The schema mismatch tag on WindowsForum.com covers discussions about Active Directory schema inconsistencies, particularly a bug in Windows Server 2025's Schema Master FSMO role that creates duplicate schema entries. These duplicates can break AD replication and cause schema-mismatch errors on older domain controllers. Administrators share troubleshooting steps, workarounds, and updates on vendor fixes. The tag is relevant for IT professionals managing Active Directory forests, domain controllers, and schema replication in enterprise environments.
A subtle but dangerous bug in Windows Server 2025’s Schema Master FSMO role is causing duplicate schema entries that can break Active Directory replication and trigger schema-mismatch errors on older domain controllers — the issue is being discussed by administrators and reported in the field...
active directory
ad replication
adprep
adsiedit
backup and recovery
domain controller
event id
exchange schema
field reports
fsmo roles
ldifde
microsoft support
migration
release health
replication
schema master
schemamismatch
troubleshooting
windows server 2025