Software Management Solution Plug-in install fails to install

Hi all,

I have deployed around thousands of Altiris agent (CMS version 7.1). It is found that almost half of hundred agents failed to install Software Management Solution Plug-in (through Settings -> Agents/Plug-ins -> Software -> Software Management -> Software Management Solution Plug-in Install). It caused fail to deploy software.

Those PCs are either 32 bit or 64 bit platfoem, andunder different Site Server.

Any hints to resolve this issue? or how can I narrow down the problem is?? Any offline download package I can try???

Many thanks.