5.7.520 Message blocked because it contains content identified as spam. AS(4810)

What report you looking for? I am not working for any company to support about it . I have not re-ally time to try providing any documentation. I just post the way I sorted it for help people.

The Microsoft was blocking everyone to sending out email yes is true … but because the files was the users tried attach were infected …. Is the reason people got emails not sent out and returned with the message on this post.

Make your own test.

I started analysed just files when was attached to the email was returning with the code .
emails I was sending from iPhone was not returning the emails with same code . than the Mozilla Firefox in the computer same story no problems.

I am sending everything now and no problems at all .

What is a Trojan injector?
Injector trojans insert malicious code into processes running on a computer in order to perform various actions, such as downloading additional malware, interfering with web browsing activities or monitoring the user's actions.


I was over two days trying find the cause and solution of this problem myself.

Is definitely the trojan as the problem here.

The only causes I can say I got infected.


extension applications on the opera browser or the https://ewelink.cc app …. That seems change configurations in my local network configuration I identified as trying to configure the smart plugs ….
read it : https://medium.com/@s12deff/trojan-backdooring-injecting-dll-hooks-into-windows-native-apps-d4b878712166


I don’t trust this app anymore .. In past I noticed a possible attack as my smart plugs started turn alone. apparently the ewelink server is not that secure. any way. I remove this smart device from my local network…. If you every use it crat a VPN not attach any CCTV camera or those smart plugs in the network you share computers.

Follows the sequence:

Reset settings in each computer you have at home …. As I found same problems in other computers that was attached to my local area network …
do this test in all computer used in the place as it seems was spread in the network of my house only in computer with windows.

use the windows defender and other security has in the windows when you write virus in the windows bar you will see all options .

additional use it .
https://www.eset.com/int/home/online-scanner


https://www.malwarebytes.com


https://keonesoftware.com/tutorials/remove-malware-opera/