Avast Paid version blocking networked computers

We renewed and updated our Avast yesterday on 2 office computers.

Computer “A” has the accounting data on it, which computer “B” accesses.
Today, computer B can’t access the accounting data unless I disable Avast on computer A.
I assume I need to make an exception somewhere but I can’t figure out where.

Is this AIS ?

If so open the GUI
Go to Tools > Firewall > Settings
Allow Internet connection sharing mode and Connections with friends

thanks that worked