Hello,
This Issue occurs due to either
- Upgrade schedule badly configured
OR
- DNS issues.
I would request you to perform the steps provided below:
- Access the install packages tab and remove the upgrade packages that has been added;
- Add the packages again;
- Set new period of time time for SEPM to provide the upgrade packages to the clients.
If the DNS error is shown in SylinkMonitor, try to add the SEPM's IP address and name into hosts file as workaround but also verify if the DNS server registries are correctly configured.
Reference Article:
Auto upgrade does not work when migrating from SEP 11.x to 12.1
http://www.symantec.com/docs/TECH172779
Hope that helps!!!