Hi,
For the "separate Task Server" case:
"Altiris Client Task Server Agent": XP and 2003 OS is not supported for the Task Server in 7.6. You need to have MS .Net Framework version 4.5.1 to be able to upgrade Task Server.
"Deployment Task Server Handler": this one depends on a Task Server plugin - as soon as TS will be upgraded to 7.6 version, DS Task Server Handler should be upgraded automatically.
"Power Scheme" and "Software Management Solution": check if computers listed in corresponding policies (dbl-click to target under "Apply To" and press "Update Results")
Settings -> Agents/Plug-ins -> Power Scheme -> Power Scheme Task Plug-in Upgrade
Settings -> Agents/Plug-ins -> Software -> Software Management -> Software Management Solution Plug-in Upgrade
If computers are listed, then on a client side dbl-click to SMA icon and check Software Delivery tab - where the corresponding packages downloaded and that's the execution status?
HTH,
Alex.