Hi Admin,
We want to restrict distribute group not to receive internet mails, but the internet mails are still going through even if the option"only senders inside my organize" is selected. The part of mail header is below,
X-MS-Exchange-Organization-AuthSource: myexchange.com
X-MS-Exchange-Organization-AuthAs: Internal
X-MS-Exchange-Organization-AuthMechanism: 10
The value of X-MS-Exchange-Organization-AuthAs is configured as "Internal" other than "Anonymous" from internet mails. Maybe this is the root cause, but I don't know how to resolve it. Currently the internet mails are first checked by our symantec mail gateway then transfer to our CAS server (myexchange.com) as above.
Could somebody instruct me on this?
Many thanks in advanced.
Leon
Leon