When a Symantec Endpoint Protection Manager (SEPM) version 12.1 RU3 is in the process of downloading the replication changes (filename: data.zip) from the remote SEPM with which it is replication and the download is interrupted (for example, the remote SEPM loses its network connection) partway through the download, the replication task status stays at "Downloading(10%)" indefinitely.
The SEPM which was downloading the replication data file does not attempt to replicate again until its services are restarted.
This issue is fixed in Symantec Endpoint Protection 18.104.22.168 (RU4 MP1). For information on how to obtain the latest build of Symantec Endpoint Protection, see Download the latest version of Symantec Endpoint Protection.
To work around this issue please do the following:
This issue may be worked around by restarting the Symantec Endpoint Protection Manager service when it is stuck in the state Downloading(10%).