Sharepoint lists mirroring issue

Hi Gllme​ 

Thanks for the screenshots, they help. The Internal system error message is a generic server-side error, and unfortunately querying the Eventhouse won't return a longer ErrorMessage than the one you're already seeing.

The useful field here is OperationName in the MirroredDatabaseTableExecution monitoring table it shows which stage each table reached before it stopped.

Start with this:
MirroredDatabaseTableExecution | where Timestamp > ago(7d) | where ItemId == "<your mirrored item ID>" | summarize StagesReached = make_set(OperationName), Rows = sum(ProcessedRows), LastSeen = max(Timestamp) by SourceTableName | order by SourceTableName asc

If the failing GI_* lists stop at ReplicatingSchema, the break is at schema read. If they reach Snapshotting and then FailTable, it's the initial data load.

Also worth making explicit what your first screenshot already shows: per the documentation, an empty Last completed value means the table isn't yet mirrored. Combined with Rows replicated = 0, your GI_* lists have never completed an initial run — so this is initial load failing, not incremental replication drifting.

The naming split is your strongest clue. COI_* replicates and GI_* doesn't, under the same mirrored item and the same capacity. Compare one working list against one failing list:

• Are the GI_* lists on a different SharePoint site or site collection?
• Are any of them actually Document Libraries rather than lists? The documentation notes Document Library data is surfaced in OneLake through shortcuts rather than being replicated, so it follows a different path.
• Do they differ in columns or data volume?

As an isolation test, mirror one failing GI_* list on its own into a new mirrored item. If it fails alone, we can focus on that list or site rather than the whole item.

One thing not worth chasing: special characters in column names are documented as supported, via Delta column mapping.

If the single-list test still returns only SystemError, I'd open a Microsoft support ticket with the ArtifactId, SequenceNumber, UTC timestamps, workspace and tenant details, and the monitoring log output those are correlation identifiers the service team can match against backend telemetry. SharePoint List mirroring is still in preview, so it's worth checking the known issues list first too.

• Mirrored database operation logs
• Monitor mirrored database replication
• Mirroring SharePoint List (preview)

Best regards,
C Srikanth
Community Support Team