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On my Wordpress site I've run into a problem in the last day or so, where emails simply fail to send. Before today it was running flawlessly for two months. The account information/password/username etc have not changed in that two months.
I'm using a Wordpress plugin called WP Mail SMTP to facilitate the sending of all outgoing emails. The error log I'm getting from the email test on that is as follows:
Versions:
WordPress: 5.3.2
WordPress MS: No
PHP: 7.3.14-5+0~20200202.52+debian9~1.gbpa71879
WP Mail SMTP: 1.8.1
Params:
Mailer: smtp
Constants: No
ErrorInfo: SMTP Error: Could not authenticate.
Host: smtp.office365.com
Port: 587
SMTPSecure: tls
SMTPAutoTLS: bool(true)
SMTPAuth: bool(true)
Server:
OpenSSL: OpenSSL 1.1.1d 10 Sep 2019
SMTP Debug:
2020-02-10 16:36:56 Connection: opening to smtp.office365.com:587, timeout=300, options=array ()
2020-02-10 16:36:56 Connection: opened
2020-02-10 16:36:56 SERVER -> CLIENT: 220 LNXP123CA0008.outlook.office365.com Microsoft ESMTP MAIL Service ready at Mon, 10 Feb 2020 16:36:55 +0000
2020-02-10 16:36:56 CLIENT -> SERVER: EHLO www.*****.com
2020-02-10 16:36:56 SERVER -> CLIENT: 250-LNXP123CA0008.outlook.office365.com Hello [***]250-SIZE 157286400250-PIPELINING250-DSN250-ENHANCEDSTATUSCODES250-STARTTLS250-8BITMIME250-BINARYMIME250-CHUNKING250 SMTPUTF8
2020-02-10 16:36:56 CLIENT -> SERVER: STARTTLS
2020-02-10 16:36:56 SERVER -> CLIENT: 220 2.0.0 SMTP server ready
2020-02-10 16:36:56 CLIENT -> SERVER: EHLO www.zestpromotional.com
2020-02-10 16:36:56 SERVER -> CLIENT: 250-LNXP123CA0008.outlook.office365.com Hello [***]250-SIZE 157286400250-PIPELINING250-DSN250-ENHANCEDSTATUSCODES250-AUTH LOGIN XOAUTH2250-8BITMIME250-BINARYMIME250-CHUNKING250 SMTPUTF8
2020-02-10 16:36:56 CLIENT -> SERVER: AUTH LOGIN
2020-02-10 16:36:56 SERVER -> CLIENT: 334 VXNlcm5hbWU6
2020-02-10 16:36:56 CLIENT -> SERVER: c2FsZXNAemVzdHByb21vdGlvbmFsLmNvbQ==
2020-02-10 16:36:56 SERVER -> CLIENT: 334 UGFzc3dvcmQ6
2020-02-10 16:36:56 CLIENT -> SERVER: QmFkMzM4MzA=
2020-02-10 16:37:02 SERVER -> CLIENT: 535 5.7.3 Authentication unsuccessful [LNXP123CA0008.GBRP123.PROD.OUTLOOK.COM]
2020-02-10 16:37:02 SMTP ERROR: Password command failed: 535 5.7.3 Authentication unsuccessful [LNXP123CA0008.GBRP123.PROD.OUTLOOK.COM]
SMTP Error: Could not authenticate.
2020-02-10 16:37:02 CLIENT -> SERVER: QUIT
2020-02-10 16:37:02 SERVER -> CLIENT: 221 2.0.0 Service closing transmission channel
2020-02-10 16:37:02 Connection: closed
SMTP Error: Could not authenticate.
Does anyone have any ideas at all? I'm completely at a loss here.
Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
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Hello Adam,
Do you have any related information to share with us?
Thanks,
Anna
Hello Adam,
Given this situation, I consider you may login Outlook Web App with impacted account to see if emails can be sent.
If Outlook Web App works well, then check firewall settings, anti-virus or related apps on your server and network, make sure all Office 365 related traffics are allowed: Office 365 URLs and IP address ranges, for some SMTP relay issues are caused by network settings.
You may also refer to this article for troubleshooting: Fix issues with SMTP client submission.
Besides, is there any organization-wide changes made recently? If convenient, use a different Office 365 account to see how it goes.
Best Regards,
Anna
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