Outlook 365 and Google Apps losing connection when behind the ICC

Users may find that when they have enabled the Anonymous Proxy Guard, Outlook 365, Google Apps, and other similar services. They will either not properly connect to their services, or they will routinely lose connection. This may cause numerous functions of these services to become unusable.


The Anonymous Proxy Guard is designed to watch for HTTP/TCP traffic over non-standard ports, and block that traffic. When this occurs to legitimate traffic, one must create a rule to send that traffic to the Web Filter. Please see the document at the following link to learn how to send this traffic to the Web Filter. 

Unauthorized HTTP(S) Traffic Blocked on Port


These are the following ports you should create Application Signatures for, to send said traffic to the Web Filter.

Outlook 365:

Mail Routing Port: 25

Outlook Web App: 10106

SMTP Relay Port: 587

IMAP Port: 143

IMAP Port: 993

POP 3 Port: 995

Lync Application sharing and file x-fer Ports: 50040:50059

Google Apps:

SMTP Incoming Server Port: 995

SMTP Outgoing Server Port for TLS/STARTTLS: 587

SMTP Outgoing Server Port for SSL: 465

IMAP Incoming Server Port: 993


Please note that if you have already added an initial Application Signature to the Traffic Flow Rule Set to open a port for Outlook 365 or another application, you should NOT add a second Signature for the same port used by a different application. The original Signature will work properly for both applications.

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