365 servers cannot be reached. (mail.protection.outlook.com) (no ban)

Hello everyone.
I found problems reaching Microsoft 365 mail servers.
The following error occures:

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Nov 20 12:57:12 4 postfix/smtp[1592]: EED7AC1A5C: to=<p***@****.com>, relay=***-com.mail.protection.outlook.com[213.199.180.170]:25, delay=96174, delays=96158/0/15/0.26, dsn=4.4.4, status=deferred (host *****-com.mail.protection.outlook.com[213.199.180.170] said: 451 4.4.4 Temporary server error. Please try again later ATTR5 (in reply to MAIL FROM command))
I can send mail to Gmail/Hotmail/Outlook.com/Live and receive it.

Also the problem occures on other Centospanel servers.

Could it be that I need a real SSL certificate and not self signed?
When I test it on testconnectivity.microsoft.com there are no problems. Everything is in the green! (No ban)
All rbl's in the green.

Maybe the *.mail.protection.outlook.com having problems with selfsigned certificates?

Another strange issue with sending to 365 mail servers from a centospanel server.
In the log it shows it is delivered but it never reaches the inbox of the 365 recipient,

Code: [Select]

Nov 20 13:22:51 100 postfix/smtpd[8710]: 6FD9E601C4: client=localhost[127.0.0.1], sasl_method=LOGIN, ssl_username=info@***.wtf
Nov 20 13:22:51 100 postfix/cleanup[8716]: 6FD9E601C4: message-id=<4570363e9f76068003a945a18cc25b5a@***.wtf>
Nov 20 13:22:51 100 postfix/qmgr[1668]: 6FD9E601C4: from=<info@****.wtf>, size=524, nrcpt=1 (queue active)
Nov 20 13:22:51 100 postfix/smtpd[8710]: disconnect from localhost[127.0.0.1]
Nov 20 13:22:51 100 postfix/smtpd[8710]: connect from unknown[185.125.6.105]
Nov 20 13:22:53 100 postfix/smtp[8717]: 6FD9E601C4: to=<daniel@*****.nl>, relay=****.mail.protection.outlook.com[213.199.154.138]:25, delay=1.9, delays=0.05/0.04/0.2/1.6, dsn=2.6.0, status=sent (250 2.6.0 <4570363e9f76068003a945a18cc25b5a@****.wtf> [InternalId=54335631262498, Hostname=VI1PR07MB1088.eurprd07.prod.outlook.com] 6892 bytes in 0.362, 18.578 KB/sec Queued mail for delivery) Nov 20 13:22:53 100 postfix/qmgr[1668]: 6FD9E601C4: removed


UPDATE

I have replaced my certificates and when I did that I restarted postfix and was able to catch the following.

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Nov 20 19:31:40 4 postfix/smtp[13872]: certificate verification failed for ***-com.mail.protection.outlook.com[213.199.180.170]:25: untrusted issuer /C=IE/O=Baltimore/OU=CyberTrust/CN=Baltimore CyberTrust Root
Nov 20 19:31:40 4 postfix/smtp[13876]: certificate verification failed for ***b-nl.mail.protection.outlook.com[213.199.154.106]:25: untrusted issuer /C=IE/O=Baltimore/OU=CyberTrust/CN=Baltimore CyberTrust Root
Nov 20 19:31:40 4 postfix/smtp[13875]: certificate verification failed for****t-com.mail.protection.outlook.com[213.199.180.170]:25: untrusted issuer /C=IE/O=Baltimore/OU=CyberTrust/CN=Baltimore CyberTrust Root
Nov 20 19:31:41 4 postfix/smtp[13872]: 3F73DC3458: host ***t-com.mail.protection.outlook.com[213.199.180.170] said: 451 4.4.4 Temporary server error. Please try again later ATTR5 (in reply to MAIL FROM command)
Nov 20 19:31:41 4 postfix/smtp[13876]: 63DFBC3CCB: host ****b-nl.mail.protection.outlook.com[213.199.154.106] said: 451 4.4.4 Temporary server error. Please try again later ATTR5 (in reply to MAIL FROM command)
Nov 20 19:31:41 4 postfix/smtp[13877]: 716E4C3CCC: host ****l.mail.protection.outlook.com[213.199.154.106] said: 451 4.4.4 Temporary server error. Please try again later ATTR5 (in reply to MAIL FROM command)
Nov 20 19:31:41 4 postfix/smtp[13875]: 556B1C3B93: host ****-com.mail.protection.outlook.com[213.199.180.170] said: 451 4.4.4 Temporary server error. Please try again later ATTR5 (in reply to MAIL FROM command)


Hi Darkanoid,

We're currently having the same problem. Here are some topics about it:
http://answers.microsoft.com/en-us/outlook_com/forum/oemail-osend/451-444-temporary-server-error-please-try-again/6f8f7b76-34c5-416c-a0fe-81867843f7eb
https://social.technet.microsoft.com/Forums/office/en-US/cc390f73-6e8a-403d-9563-d532cba2d50f/cant-send-email-451-444-temporary-server-error-please-try-again-later-attr5?forum=exchangesvrclients

Yes I have seen those to. 
It seems that it is a certificate issue with microsoft. Also more people are experiencing the same.

My little brother even suggested a man in the middle attack.

Is your server also located in the Netherlands?

No all are based in Germany but senders mail are .nl tld's
Yours?

Servers, senders and recipients all NL. Some of the recipient domains don't any have problems, but they are running on different IP addresses.

Everything works fine when using this tool so I guess it's a regional problem.

Looks like it 

Lets see how fast MS will pick this up.

That looks like Office 365 are Gray listing

Nov 20 19:31:41 4 postfix/smtp[13875]: 556B1C3B93: host ****-com.mail.protection.outlook.com[213.199.180.170] said: 451 4.4.4 Temporary server error. Please try again later ATTR5 (in reply to MAIL FROM command)

Yeah I know but when you look at https://testconnectivity.microsoft.com/ there are no problems. Also allot of other people are experiencing this starting from saturday.

At this time it works for me, but there are still people complaining.

http://answers.microsoft.com/en-us/outlook_com/forum/oemail-osend/451-444-temporary-server-error-please-try-again/6f8f7b76-34c5-416c-a0fe-81867843f7eb

Oh I was to fast.
Again same problem. So its not solved yet.
I dont think anyone has a clue what it is.

Do you have the correct DNS records for your domain ?
SPF,DKIM,PTR

Yes but now I get the report that im blacklisted. Funny part is that my ip in not in any MS banlist at testconnectivity.microsoft.com
More people are reporting the same.