If you want to stop using Folder Guard on the network, do NOT delete Folder Guard GPO or uninstall Folder Guard software from the server as the first step! Before that, you need to undo the configuration steps:
First, run Folder Guard software on the server, open the Folder Guard GPO with it, and set the status of the GPO to Not Configured. This will cause the Folder Guard settings to be removed from the client computers after the next Group Policy update.
Second, edit the Folder Guard GPO with Group Policy Editor on the server, and delete the Folder Guard MSI packages from the GPO. This should uninstall Folder Guard software from the client computers after they've updated their Group Policy and restart.
Now wait for the Group Policy to be updated on the client computers, or use the gpudate command on them to force the updates. Restart the client computers after the update to force them to actually uninstall Folder Guard software.
After all client computers performed this procedure, use Group Policy Management tool on the server to unlink the Folder Guard GPO, and then delete the GPO itself. If necessary, use Windows Control Panel on the server to uninstall Folder Guard, and that should complete the removal procedure.
Please consult your Windows Server documentation for more information on GPOs and Group Policy.