Please let me have some advice / help on the failed installation of EndPoint 12.1 on a Windows 7 PC.

One of the Windows 7 client warned on auto-protection disabled. Decided to re-install EndPoint.

Removed the client from SEPM and deploy again by push but still auto-protection disabled.

Then login locally on the Windows 7 PC and removed EndPoint and tried to re-install but the local installation failed.

Executed cleanwipte and re-install and still failed.

Attached the SEP_INST.log in 7zip format

Attachment(s)

SEP_INST.7z   92 KB 1 version

Have you try install unmanaged sep client ?

Troubleshooting client installation failures

Thanks Sumit G, but symhelp showed no problem for local install. It shows that possible problem with remote push for ports with limited scope.

You are trying very old version on your system. Lates version is 12.1 ru4 mp1b which is available in file connect.

Your log is similar as cmmented by Mithun

https://www-secure.symantec.com/connect/forums/wizard-was-interrupted-symantec-endpoint-protection-could-be-completely-installed-1#comment-6634661

Check comment

ScriptGen: ShowServiceProgress() reset script failure event.
ScriptGen: ShowServiceProgress() is returning an error (so close to the end!)
CustomAction ShowServiceProgress returned actual error code 1603 (note this may not be 100% accurate if translation happened inside sandbox)
MSI (s) (34:1C) [10:22:22:322]: User policy value 'DisableRollback' is 0
MSI (s) (34:1C) [10:22:22:322]: Machine policy value 'DisableRollback' is 0
Action ended 10:22:22: InstallFinalize. Return value 3.

Check this Thread (Almost the same Issue): 

https://www-secure.symantec.com/connect/forums/sep-121-client-installation-failure

Also, 

Disable UAC and Windows Firewall and Try Creating a custom setting under the “Client Install Settings” options to not use “Add the program to the Start Menu”, leave this unchecked.

OR / AND

Deploy a client install package with "Remove all previous logs and policies, and reset the client-server communications settings".

http://www.symantec.com/docs/TECH165801

If the install is successful, manually create the shortcut on the desktop that points SymCorpUI.exe.

Post the SIS_INST.log as well

What logs do I need to gather in order to troubleshoot a failed SEP 12.1 client installation?

Try the lates version an check the status