XG Firewall Block Outlook Connections to an external Mail Server using IMAP and SMTP

I need to replace an old Firewall in a costumer with XG Firewall. All the internal Clients are using proxy configuracion so i can't change this (becouse they use web restrictions) ... and i have to activate the proxy rule in the XG Firewall  

All the clients use Outlook to conect to an external  Email Server with IMAP and SMTP services.    mail.xxxxx.gov.py

If i activate the proxy  in the XG Firewall : 

Web Policy:    Allow  All     Use web proxy instead of DPI engine      and     Decrypt HTTPS during web proxy filtering  or

Web Policy:    none     Scan HTTP and decrypted HTTPS      Use web proxy instead of DPI engine      and or no    Decrypt HTTPS during web proxy filtering 

Also configuring the windows   Internet Propieties > Conexions > LAN configuration  > proxy with the  port 3128 and  XG Internet  Address

All the conection using outlook  to conect to the mail server are block.... (I can access to any web page  but no email with outlook)

I try with adding a  FW rule to the email address with no proxy but still blocking the conections 

Only when i activate the proxy in the XG ... all outlook connections to the email server are block

This picture shows an test account sophos@xxxxx.gov.py   that i'm using  to solve this problem and the error message

I try installing a CA certificate in windows but looks do not solve this ...

Using the XG Firewall and Web Policy (no Web mail)  have the same problem with my own email exchange (office 365)  account  with outlook (no proxy)  but adding the exception as the KB-000038173 shows solving the problem....I also try to add an exception to the  mail.xxxxx.gov.py  but still no conection using the XG as  proxy

I may skip something..

What can be the problem ??or better .. the solution...