Recently the amount of obvious junk mail getting through Exchange has gone way up, and we noticed that the message headers are missing the SCL & SPF that they had in the past. We tracked it down to an exact day & time that the headers stopped
getting added, but we don't know what changed. In Outlook 2010, messages from before that time have headers like this:
X-MS-Exchange-Organization-PRD: bounce.linkedin.com
Received-SPF: Pass (mail.mydomain.com: domain of
messages-noreply@bounce.linkedin.com designates 216.52.242.153 as permitted
sender) receiver=mail.mydomain.com; client-ip=216.52.242.153; helo=mail-02-pao.dyndns.com;
X-MS-Exchange-Organization-SCL: 3
X-MS-Exchange-Organization-PCL: 2
X-MS-Exchange-Organization-Antispam-Report: DV:3.3.5705.600;SID:SenderIDStatus Pass;OrigIP:216.52.242.153
X-MS-Exchange-Organization-AuthSource: mail.mydomain.com
X-MS-Exchange-Organization-AuthAs: Anonymous
But those headers have disappeared and we don't know why. We checked the server event logs on that day and didn't see any Exchange hotfixes or service packs installed, or anything obvious. This is on a Hub Transport server with the anti-spam scripts installed. We checked the Organization Configuration --> Hub Transport --> Anti-Spam tab and the features are enabled:
Content Filtering: Enabled
Recipient Filtering: Enabled
Sender Filtering: Enabled
Sender ID: Enabled
Sender Reputation: Disabled
IP Allow List: Disabled
IP Allow List Providers: Disabled
IP Block List: Disabled
IP Block List Providers: Disabled
Any suggestions for things to check? Thanks!