Can't update & Fortimail, fortiweb and forticlient EMS from fortimanager?

Hi,

I have an issue updating this devices for AV other softwares. But it works like charm for all the fortigates of my corporation. I think the configuration is correct for the devices and fortimanager. I can provide informations about the configuration if you need more detail.

Forticlient EMS 1.2

FMG 5.6.1

Thank you in advance.