MS Exchange MTA

Please help,
My users cannot send and receive email message. I’ll check the Event Log and i found out this message:

Event ID:9277
Source:MS Exchange MTA

The MTA has issued an RPC cancel call for thread 26, Locality Table index: 63, time[ms]:6677190, cancel result:0 [Aspire mtasend ncacn_ip:201.102.23.2 [1074] Base IL (14).

What sould i do?

Thanks in advance.