DSA successfully Mailbox Enables objects yet returns Error 0xe300000c. Cannot apply Mailbox Secur (4312052)

While running a DSA synchronization with exchange options enabled, you receive the following error:

"Error 0xe300000c. Cannot apply Mailbox Security Descriptor to Exchange Store (Server=APS001.ms.ds.uuu.com, MailboxGUID=0DFBEEF8C54C104F8F3F156AACB8D199, HomeMDB=<GUID=7482a97a70df234e95e13fa4e3fcbc03>;CN=Mailbox Store (APSE9294),CN=First Storage Group,CN=InformationStore,CN=APS001,CN=Servers,CN=First Administrative Group,CN=Administrative Groups,CN=UHG-ExchangeMail,CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=ds,DC=uuu,DC=com). RPC error 0x6ba. The RPC server is unavailable.

But after checking the target object you find that it has been successfully Mailbox Enabled."

Name resolution is usually the issue with "The RPC server is unavailable Error (0x800706ba)".

Verify that you can successfully ping the servers and that the 'nbtstat -a servername' command can successfully contact the Exchange server. The nbtstat command will resolve the NETBIOS server name to an IP address, if DNS/WINS are configured correctly. If nbtstat -a returns "Host not found", this indicates that it cannot resolve the NETBIOS name from the IP address.

Usually the issue with "The RPC server is unavailable (0x800706ba)"error and -a will fail, especially within an environment that has disjointed namespaces. Resolve name resolution.

Note: As a workaround an LMHOST files can be used but best practice is to resolve the name resolution issues within the environment.