Hello,

In our Exchange 2013 environment, there are two Forefront UAG servers which publish OWA, Outlook Anywhere to Internet.

The customer has a requirement, the abc security group can only visit mail at company. Out of company mail access is forbidden.

I found in the publish application, there is a Authentication tab. the currently setting is "All authenticated users" allowed.

Can I change the setting below to get the goal?

Authenticated users    Allow

ABC group                 Deny

I think that should be fine, but I don't have test servers to have a test.

Any input will be highly appreciated.

Hello, 

Yes that should be sufficient, for more information you can use the link below.

https://technet.microsoft.com/en-us/library/ee406224.aspx?f=255&MSPPError=-2147217396#BKMK_Authorization

Let me know, how it goes.

P.S: Please mark as answer or Vote as helpful if you find so.