Core issue
This cosmetic error occurs due to the presence of Cisco bug ID CSCed83628.
In a scheduled replication scheme, a secondary server incorrectly records an error in the replication log when a scheduled replication does not occur because no changes occurred on the primary server. For example, this can occur when the primary and secondary servers are only configured to replicate the user database and network configuration, and then a change is made to the network configuration on the primary server but not in the user database. At the next scheduled replication, the primary server correctly sends only the network configuration, but the secondary server logs an error message that the user database was not received.
Resolution
This is a cosmetic error message and can be ignored as what it reports is incorrect. This cosmetic issue is fixed in the 4.01 release of CiscoSecure ACS for Windows.
In order to download CiscoSecure ACS for Windows version 4.0(1.27), open a service request with Cisco Technical Support.
Cisco Secure Access Control Server (ACS)
ACS for Windows version 3.3
ACS for Windows version 3.2