How to create the Report of the system which are not Active from last 30 days?

Go to Report then Inventory Agent - Inventory Capture - (Inactive Machine)

As i have seen on Server this Report is display, try may be it help you.

hi,

You can found under.

Reports->All reports->Discovery and Inventory->Inventory->Cross-platform->Inventory Agent->Inventory Diagnostics->Under you can find (Computers that have not reported inventory in last N days)

Altiris Report: How Works 'Inactive Machines' report ??

https://www-secure.symantec.com/connect/forums/altiris-report-how-works-inactive-machines-report

Check the forum

It also help you to find the Report

https://www-secure.symantec.com/connect/forums/altiris-report-how-works-inactive-machines-report