I am receiving email in my inbox which are spam but they do not seem to have a spam score. They seem like they have somehow bypassed MSME.
I have in Gateway antispam setting add spam score indicator always and attached spam report always.
Some messages that are not spam do have a spam report details in the header for example the one below but some (the one that is spam) have no mention of NAI
X-NAI-Spam-Rules: 6 Rules triggered
DTP_2WD=0.2, TRK_NCM1=0.2, THREAD_INDX_INVALD_VAL=0.1, EDT_SDHA_ADR_FRG=0,
X-NAI-Spam-Version: 126.96.36.19909 : core <5882> : inlines <5548> : streams
<1723771> : uri <2337881>
Thanks for your help, jbason.
If outlook is pulling mail from multiple sources (e.g. additional accounts like pop/imap) - only the mail coming from an external source through Exchange Server will have possibility to get scanned for spam.
Internal mails are not scanned for spam.
AntiSpam settings gives option for when to attach spam report (and whether verbose report or not) - unless "to all mail message" not all mail scanned for spam will get this.
AntiSpam advanced settings has a setting for max mail size presented to spam engine - default is 250KB. (if using default then a mail item at overall size 275KB
is not even presented to spam engine therefore not scanned and therefore cannot be marked)
The mail that does not seem to have been scanned has a attachment of 200kb so I will increase the maximum size to 500kb and see if that helps.