DSM fail to synchronize AD account, and check detailed error information, prompting "UPN is empty, sAMAccountName=xxxx, is not consistent, do not allowed to synchronize".
Find the AD account, and manually modify the upn attribute value and sAMAccountName attribute value as the same, then synchronize again.
The reason might the synchronous third-party LDAP organization user attribute value UPN and sAMAccountName is inconsistent. The two attribute value of third-party LDAP (MS AD or Novell eDirectory) user object is: UPN and sAMAccountName. Now use AD user attribute to introduce.
UPN and sAMAccountName are the same by default. Because the user establishment is not standard, when the UPN and sAMAccountName value is not the same, the user will not be synchronized by DSM, and will prompt the detailed synchronous error information.