When using the All IIS Servers site, offline computers are returned when enumerating the site. When a gathering job runs you see in the InTrust server event log that it is trying to push agents to the offline computers.
This is due to the nature of the All IIS Server site. InTrust must query the running computer to see if it is an IIS server. When the computer can not be enumerated it is included by default. This will not cause an issue on any offline computers that shouldn't be in the site as the install of the agent will fail. If it were online, InTrust would find it was not an IIS server and not include it. The only downfall is that you will see the agent install to offline computers fail in the log.
We can avoid getting workstations returned by enumeration by setting up a filter on the site. When setting up the filter, make sure that any "NOT"' exclusions you put in to exclude your offline computers come before the inclusion of the IIS Servers.
1. Navigate to "Quest InTrust Manager" | "Configuration" | "Sites" | right-click on the "All IIS Servers" site | select "Properties"
2. Select the "Filter" tab and setup the filter similar to the screenshot below. Exclusions need to be above the inclusion for "Microsoft IIS Server", because of how this filter works.