Hi there,
Generally issues can occur if you have had previous Norton or Symantec products on the machines in question. As these all use LiveUpdate as well - any remnants of old versions of LiveUpdate can cause problems with new installs of SEP.cloud.
For one of the affected machines, could you please browse to the following fileshare, then select, download and run the SymantecRemovalToolExtractorV2.exe from the SEP Removal Tool folder:
URL: https://fileshare.symantec.com
Username: SHEP1
Password: Password123#
Running this will remove all aspects of the service from the machine, including LiveUpdate. If not all the items are ticked off initially you may need to reboot the machine and run it again. Once this has been done please re-install and see if the issue is still present - hopefully this should sort it for you.
Kind regards,
- FP