After verifying backups by restoring files to alternate location, it sometimes happens that we can not remove restored files by 'You require permission from TrustedInstaller to make changes to this file' error as Figure 1. This most likely happens when restoring system or program files. Owner of unremovable files is TrustedInstaller user, and only this user has full control right.
Figure 1 File Access Denied
Figure 2 Owner of unremovable files
Figure 3 Permissions of unremovable files
We can manage to remove files by changing owner and permissions of unremovable files. Here is an example of removing System State files restored to C:\restore(See HOWTO36039 for how to restore System State to an alternate location).
Step 1 - Open Security tab in properties window
Figure 4 Select a folder where System State files are restored
Figure 5 Click Advanced button in Seciruty tab
Step 2 - Change owner of files and subfolders
Figure 6 Click Edit button in Owner tab
Figure 7 Check 'Replace owner on subcontainers and objects'
Step 3 - Change permisson of files and subfolders
Figure 8 Click Change permissions button
Figure 9 Check 'Replace all childobject permissions ...'
Step 4 - Remove restored files
Figure 10 Delete folder
Figure 11 Delete system files
Figure 12 Completed!!