Mail Forward Failure

Dear Sir/Mdm,

I'm getting this Mail Forward Failure :

The following message could not be forwarded to for

Technical details of the failure:
5.7.0 This message was blocked because its content presents a potential
5.7.0 security issue. Please visit
5.7.0 to review our message
5.7.0 content and attachment content guidelines. ie10si5003532pad.137 - gsmtp

----- Transcript of session follows -----

Received:from ( []) by
with SMTP id 1472725755714810.7769238729196; Thu, 1 Sep 2016 03:29:15 -0700 (PDT)
Date:Thu, 1 Sep 2016 10:28:48 +0000 (UTC)
From:Caitlin G <>
Subject:RFQ // FCL

P.S: Please note that your email forwarding will be disabled if there are too many failures.

Is there a security problem that I should be worried about? :slight_frown: