OpenQuery-条件中的physicalDeliveryOfficeName

Question

在我的查询中，第二个条件不起作用，显示带有99999的字段，您能帮我吗？

SELECT *    FROM OpenQuery(AD, 
'SELECT     sAMAccountName, physicalDeliveryOfficeName
FROM        ''LDAP://ou=....''
WHERE       objectCategory=''user'' and physicalDeliveryOfficeName<>''99999'')

see image with error