What is a 550 5.7.1 error?
A 550 5.7.1 commonly refers to the IP, that is sending the email, currently is blocked from the recipients email service. It is normally blocked because the IP, at one point in time, was used to send spam to the recipients IP. If this example is the case, the recipients email service blocks the IP from future spam and notifies any senders with a 550 – 5.7.1kick-back somewhere in the returned email.
Is My IP Blacklisted?
Just because you received a 550 – 5.7.1 error does not mean your IP is blacklisted. However, it is still good practice to check your IP for blacklisting and its current reputation if you received a 550 error for verification. Please note, this is not the IP from your local machine, but the IP of your hosting server.
Tools For Blacklisting Check:
- MXToolBox: https://mxtoolbox.com/blacklists.aspx
- MultiRBL.valli.org Blacklist Checker: http://multirbl.valli.org/
Tools For IP Reputation:
- Cyren: http://www.cyren.com/security-center/ip-reputation-check
- Talos: https://talosintelligence.com/reputation_center
It is important to understand why this error occurs and to take preventative measures to ensure this can be resolved as quickly as possible. We suggest performing the following:
- Change your Email Account’s passwords to a secure password
- Update any Applications that you are using for your web hosting services
- Remove any unused Applications that you are not longer using
- Perform a virus scan on your computer
How do I remove the 550 5.7.1 error?
Unfortunately, if your IP is not blacklisted, a “delist” request to the recipients mail service is required. This includes a form with required information to be submitted to them explaining the IP is currently blocked by their service and you wish for it to be unblocked. The delist form is different for each mail service (example, Outlook, Gmail, hotmail) and once submitted, it is up to the current mail service to unblock the IP from their list.
Each email service has their own individual form to be filled out for delisting. Hostwinds technical support will gladly assist with requesting the delisting of your IP upon opening a ticket and requesting the IP be delisted for any of your Managed Services such as Shared Hosting, Business Hosting, Managed Linux, Managed Windows or a Dedicated Server.
How long will a delist request take once submitted?
This can vary depending on the results of your IP reputation. It is important to note that the request is solely in the hands of the service the delist was requested. If the IP is never delisted from their service and the IP itself is not blacklisted, a 550 7.5.1 error will continue to be kick-backed.