Endpoint Protection

I have recently discovered that SEP 14.x is no longer compatible with Windows 7. when attemping to add a managed client to a workstation using prepared exe package on a machine that never has had sep on it  the installer fails and rolls back. Management console sends new client email but live update never runs and event viewer has new entries in application. 

Errors; event ID, 34, 35, when defender product disabled changes to 36, 37. installer error 1603.

 I tried all the tricks, manually installing from media, disable defender and or essentails, clean boot etc. no luck. Then i build a new install patched it to 2019-10. and voulla it worked. management console send email and live update runs. Or so i thought. when you open the aspplication it hanges and never opens and live update never finishes 'finalizing updates'. Version 12.6 installs on original worstation with out a hitch.

updates

So when i reboot the test machine it is hung and must be crashed. When resarted client is malfunctioning, live update runs again and then it prompts for reboot as if its installed for first time.  after reboot it now appears to be working, green dot and all. Time will tell.

Errors on test machine ID 1002, sep stopped interacting with Windows and was closed.

It's still supported according to https://support.symantec.com/us/en/article.tech235706.html

Something must be affecting it... what else is installed on the Windows 7 machine?

Does it still fail if it's just Windows 7 install with the latest updates/patches installed?

on a fresh build patched to 2019-10 application  hangs and never opens and live update never finishes 'finalizing updates'. Then reboot the test machine it is hung and must be crashed. When resarted client is malfunctioning, live update runs again and then it prompts for reboot as if its installed for first time.  after reboot it now appears to be working, green dot and all.

Have you tried running the symdiag on the machine to see if there's anything conflicting? 

Basic troubleshooting here and forgive me if I missed this mentioned already but perhaps try your build on a 2nd hardware box, to rule out both randomness and hardware.  (people that argue two machines should behave identically don't understand that not all machines, even "identical" ones, will do the same thing).  

Though I suppose it should be asked:  why is your management allowing fresh installs of Win 7 at this stage in the Win 7 lifecycle?  Or maybe an automated upgrade to Win 10 is planned soon afterwards?  Otherwise they seem to want to waste your time and their money. If they keep running Win 7 past Jan 14.  If that happens you might as well not even bother installing SEP at all :)