Require Messagelabs IP source IP range (

I need a solution


Our organisation has implemented Mimecast for our email security.  We have some users who are using a application and uses it to send out emails to other users of the same application.

However, we get emails bounced back, due to Mimecast detecting a different IP address everytime the email gets sent out via Messagelabs and sees it as spoofing when it is not.

Can anyone provide the IP Source Range for Messagelabs:’s source IP range




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