Hi Ryan,
I have checked the IP against the .cloud Blacklist and can confirm that these are not listed with us and the reputation is still good after the reset I performed yesterday, I can confirm that the .cloud infrastructure would not be blocking your emails for this reason.
With the details you have provided you may wish to inform the Messaging gateway products to which the .cloud team have no access to. If you do have problems with them, you will need to raise this in their Forum:
https://www.symantec.com/connect/security/forums/messaging-gateway
Also you could provide samples to our antispam team who can update the brightmail team to help prevent further false positives.
To analyze a false positive sample, Symantec must receive the original false positive email:
•As an "message/rfc822" email attachment*
•One email attachment per submission**
Send the false positive sample as an email attachment to the following address:
CLOUDfeedback@feedback-87.brightmail.com
For more detailed information on how to submit, please take a moment to review the below article.
https://support.symantec.com/en_US/article.TECH233...
Kind regards
Kevin Brosnan
Tier 2 Senior technical support engineer