Virus Definition is not updated on any client

Hi,

We have had more than a month that the Virus Definition is not updated. I have already done several tests and nothing works and I do not know what else to do, could you help me?
I do not know if they are the ports, what are the ports that the console must have enabled to communicate with the clients?

I guess it will also be related to the FILE REPUTATION LOOKUP ALERT because it tells me that I have many clients with:
Reputation check for unproven files failed because of network errors for the last 3 days.

Regards.