It is easily to configure Security Root Keylogger to startup for a single user, or to start up as a service for all users on your computer - perfect for monitoring multiple users of a PC. This is specially useful if you do not have access to your child's account. You can still install it via your desktop and record your child's internet and surfing activity. if you want to monitor multi-users, following below steps, only 2 steps to monitor all user's activities:

Step 1:

Open Security Root Keylogger, click Options button on the main window, then select User Filter from left list. Select the users you want to monitor.


Step 2:

configure the Logs Folder have a Everyone permissions.
a. 
Open the logs folder's property dialog:


b.
then click the Security tab as shown in below.


c.
To set permissions for a group or user that does not appear in the Group or user names box, click Add. Type the name of the group or user you want to set permissions for and then click OK, as shown in below. 

*You need to enter 'EveryOne', then click OK.
*If you can not see the security tab, please visit: How Do I Get the Security tab in Folder Properties?