So if I understand correctly in all of the possible scenarios the (NI) SEPM is problem? If yes try to reinstall Liveupdate on that SEPM:
1. Remove Live update from "Add/ Remove Programs"
2. Reboot the machine
3. In Windows Explorer, if they are present delete the following folders, without saving the existing content:
- C:\ProgramData\Symantec\LiveUpdate
- C:\ProgramData\Application Data\Symantec\LiveUpdate
- C:\Program Files (x86)\Symantec\LiveUpdate 4. Install LU using lusetup.exe (execute with local admin rights - build in administrator)
5. in C:\Program Files\Symantec\Symantec Endpoint Protection Manager\bin:
- Type lucatalog -cleanup and press Enter.
- Type lucatalog -forcedupdate and press Enter.
6. in C:\Program Files (x86)\Symantec\LiveUpdate start luall.exe (execute with local admin rights)
7. Please let the Live update express session run till the end and check if any errors are occuring
8. If the session was successfull check the path: "D:\Program Files (x86)\Symantec\Symantec Endpoint Protection Manager\Inetpub\content" to see if there is any content downloaded - you should see here several folders
* Just a note a configuration of SEPM and LUA running on same box is not really recommended and can cause issues:
http://www.symantec.com/docs/TECH105076