"Copying pre-existing data completed with errors. For additional details, go to initial sync details tab."
The error message is confusing and does not reflect the actual issue behind the scene - you will never be able to figured it out what is wrong until you raise it with MS dual-write team and share the activity Id of the job with them to investigate the telemetry (you don't have access to check this one 😒) then they share the root cause. However, You can also investigate by putting a breakpoint in method validateDataSharingEnabledForEntityTableBeforDualWriteEnable() of class SysDataSharingValidation./// <summary>
/// Validates that cross company data sharing is not enabled when enabling Dual Write.
/// </summary>
/// <param name = "_entityName">The name of the entity containing the table being enabled</param>
/// <param name = "_tableName">Table in entity</param>
/// <param name = "_dataAreaId">Company info</param>
[SubscribesTo(classStr(BusinessEventsRegistrationBase), staticdelegatestr(BusinessEventsRegistrationBase, onTableEnabled))]
public static voidvalidateDataSharingEnabledForEntityTableBeforDualWriteEnable(str _entityName, str _tableName, DataAreaId _dataAreaId)
{
SysDataSharingOrganization sysDataSharingOrganizationTable;
SysDataSharingRuleEnabledsysDataSharingRuleEnabledTable;
select firstonly SharedTableName from sysDataSharingRuleEnabledTable
wheresysDataSharingRuleEnabledTable.SharedTableName == _tableName
join DataSharingPolicy, DataSharingCompany from sysDataSharingOrganizationTable
where sysDataSharingRuleEnabledTable.DataSharingPolicy == sysDataSharingOrganizationTable.DataSharingPolicy
&& sysDataSharingOrganizationTable.DataSharingCompany == _dataAreaId;
if (sysDataSharingRuleEnabledTable)
{
throwerror(strFmt("@DataSharing:CrossCompanySharingError", _entityName, sysDataSharingOrganizationTable.DataSharingPolicy));
}
}