I use pavement layers to send proposals and they are being blocked

Question

The first proposal I sent I received a notice that my email was undelivered with an error of 550 5.7.1

it said my Ip address was on a block list (S3150) How do i get removed so i can send proposals to my customers

Answer 1

Hi @Colton Erskine, 

Thank you for posting your question in the Microsoft Q&A forum. 

Regarding the error 550 5.7.1 you received when sending your proposal: 

The error 550 5.7.1 (S3150) indicates that the IP address used by your email server has been blocked by Outlook.com/Hotmail’s automated spam filtering systems. This is something Microsoft uses to protect their users from unwanted or suspicious mail. 

To resolve this, your email administrator will need to request removal of the IP address from the block list. Here’s how: 

How to Request Delisting 

1. Go to Microsoft’s official delist portal:  https://sender.office.com/ 
2. Follow the on‑screen steps carefully. 
3. Enter: 
   • The blocked IP address shown in the non‑delivery report (NDR) 
   • An email address that received the bounce message 
4. Submit the form for review. 

You could refer to this article for a better view : Remove yourself from the blocked senders list and address 5.7.511 Access denied errors - Microsoft …  

Please note that forum moderators do not have access to user accounts, and we cannot assist with login issues, password resets, account reactivation, or remove IP addresses from block lists. Our role is limited to providing guidance based on the information you share. 

Thank you again for your time and understanding. While my initial response may not resolve the issue immediately, I’d like to gather more details about your situation so I can assist you more effectively.       

I really appreciate your patience, and I’m here to help. Looking forward to your response.  

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