Try adding the setting PageSize="1000" to your query parameters. For example:
<ActiveDirectoryQuery><Directives WhereToBind="LDAP://CN=Users, DC=test, DC=com" Filter="(objectCategory=user)" SearchScope="onelevel" PropertiesToReturn="cn" PageSize="1000"/></ActiveDirectoryQuery>
By default Active Directory only allows for a single page of 1000 results. By explicitly setting this value multiple pages (and hence all results) are returned.
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Yes. The ON CHANGE ONLY option on the Active Directory Receive Adapter provides this feature. A message is submitted to your BizTalk application only when the results of the query you have specified change. This feature provides a great way to trigger orchestrations and keep information in your Enterprise Applications synchronized.
There is also a REAL-TIME mode that gets events from Active Directory asynchronously and submits them to BizTalk as they happen.
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