...the bright yellow SEP icon appears on the dock and bounces until you acknowledge it.
Do you mean the LiveUpdate icon? The behaviour you are describing sounds like a missed event LiveUpdate running after bootup, one that does not have the "quiet" switch attached to it.
Are these clients installed as standalone clients (that is to say, not being managed by a Windows SEPM server)? If they are unmanaged, it really sounds to me like the default scheduled LiveUpdate (which is not quiet) is persisting. If managed, let me know; I don't want to go into that detail if it does not apply.
I've tried creating a weekly schedule (Monday, 3am, All Products, Quiet) using the sudo symsched command in Terminal as sandra.g described, but it still comes back (in this case, on Thursday) and does the same routine as described above. I've also verified with the GUI that the schedule is indeed active and setup correctly.
I'm confused. The only way you should be seeing a schedule in the GUI created using symsched command line (in conjunction with sudo) is if you are logged in as root. Is this the case?
Not that it should matter, but do these machines pretty much have just a single user each?
On one of the machines having this issue, please open a Terminal window and enter:
sudo symsched -l
(that's a lowercase L) Then copy what you see there into a message on this thread (or attach a screen shot to this thread). Thanks.
sandra