I've searched the forums but haven't found exactly this use-case. I'm trying to send an email to a domain, but it's being rejected by its MTA with the message
554 5.7.1 Service unavailable; Client host [..] is blacklisted
When I visit the lookup page (included in the message) at https://www.sophos.com/en-us/threat-center/ip-lookup.aspx I get redirected to https://www.sophos.com/en-us/labs (presumably this is updating tools) but it shows a green "OK" for my IP. I've also checked all blacklists and the IP has a good reputation.
I'm a bit stuck - I cannot send email (IP is blocked) and I cannot unblock (IP is not blocked). Never the less, I would like to send email. Perhaps someone has a tip on what I might be missing?
Jist to update the community, this issue got resolved after opening a case with labs, and they confirmed that the IP/Domain was incorrectly being blocked, after that, they allowed the IP/Domain…
Thank you for contacting the Sophos Community.
Check on a 3rd party tool such as MX toolbox if your IP or Domain is being blacklisted, this might be the case.
If your domain and IP keep showing as good please share you Domain and Public IP via PM if you want, so I can check with Labs.
Jist to update the community, this issue got resolved after opening a case with labs, and they confirmed that the IP/Domain was incorrectly being blocked, after that, they allowed the IP/Domain.