Transport rule applied false positive

Hi everyone,

In my Org. I have Exchange 2010 and 2013 servers.

I have created two transport rule:

• Block spesific attachments extensions (on Exchange 2010 - for mailboxes located on that server).

This rule also is applied on 2013 Mailbox servers.

Now I'm getting some requests from my users - the rule is applied where it should not.

Could you please explain, how can I track, WHY the rule is applied? It rejects the messages where no attachments at all..