Troubleshoot method for offline clients

There are many reason for the client offline status. Below are the some reason with resolution

1. Systems are in unmanage condition.
https://www-secure.symantec.com/connect/downloads/solution-doc-manage-unmanaged-system-sep-1106005

https://www-secure.symantec.com/connect/downloads/sylink-replacer

https://www-secure.symantec.com/connect/downloads/script-convert-unmanaged-system-managed-system

https://www-secure.symantec.com/connect/downloads/image-installation-system-problem

2. Client communication issue.

Port is not open for the same systems Vlan. Open the port 8014 from firewall (http://management_server_address:8014/secars/secars.dll?hello,secars) Answer Come Ok then port is opened

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Troubleshooting Client Communication with SEPM

Symantec Endpoint Protection: Troubleshooting Client/Server Connectivity

3. System is power Off/Sleep Mode
Manually go to the place of system and wake up the system. Wake on lan utility is alos helpfull in same.

4. System in Safe Mode.

Best solution for the safe mode is to disable this option through group policy because USB is accessible in Safe Mode and it against the security.

5. Proxy Setting issue
 

Below step are helpfull in in Proxy Block issue

Checked the client status: offline
Took the backup of the registry
Delete the following registry keys:
 HKEY_USER\.DEFAULT\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Connections\DefaultConnectionSettings
 HKEY_USER\.DEFAULT\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Connections\SavedLegacySettings
Set the proxy enable in the registry to 0 under HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings
Uncheck the proxy setting option in the internet options settings.
Reboot the system.
Check the client status : online/reporting to the server