SEP Package download status when deployed through SEPM

To verify that a package is downloading to clients, look for the Program FilesSymantecSymantec Endpoint ProtectionDownload folder to appear and be populated with either a .dax or .zip file. When the file disappears, the upgrade process is starting on the clients. The process can take 10 or more minutes.

More resources:

1. Symantec Endpoint Protection: Troubleshooting Client/Server Connectivity
2. Troubleshooting Content Delivery to the Symantec Endpoint Protection client
3. Content Cache Control