Hi, we are using libcurl in version 7.71.1 (32 bit) on Windows to send email using SMTP. The login fails to some customers office365.com server. Here is the log. I replaced some sensitive information with xxxxxxx, please apologise.
CURL: Trying 52.97.201.114:25... CURL: Connected to smtp.office365.com (52.97.201.114) port 25 (#0) CURL: 220 AM9P195CA0024.outlook.office365.com Microsoft ESMTP MAIL Service ready at Thu, 21 Sep 2023 13:58:47 +0000 CURL: EHLO XXXXXXXXXX-102 CURL: 250-AM9P195CA0024.outlook.office365.com Hello [185.173.180.160] CURL: 250-SIZE 157286400 CURL: 250-PIPELINING CURL: 250-DSN CURL: 250-ENHANCEDSTATUSCODES CURL: 250-STARTTLS CURL: 250-8BITMIME CURL: 250-BINARYMIME CURL: 250-CHUNKING CURL: 250 SMTPUTF8 CURL: STARTTLS CURL: 220 2.0.0 SMTP server ready CURL: EHLO XXXXXXXXXX-102 CURL: 250-AM9P195CA0024.outlook.office365.com Hello [185.173.xxx.xxx] CURL: 250-SIZE 157286400 CURL: 250-PIPELINING CURL: 250-DSN CURL: 250-ENHANCEDSTATUSCODES CURL: 250-AUTH LOGIN XOAUTH2 CURL: 250-8BITMIME CURL: 250-BINARYMIME CURL: 250-CHUNKING CURL: 250 SMTPUTF8 CURL: AUTH LOGIN CURL: 334 xxxxxxxxxxxxxxxx CURL: xxxxxxxxxxxxxxxxxxxxxx== CURL: 334 xxxxxxxxxxxxxxxx CURL: xxxxxxxxxxxxxxxxx= CURL: Operation timed out after 8002 milliseconds with 0 out of 0 bytes received CURL: Closing connection 0 CURL: schannel: shutting down SSL/TLS connection with smtp.office365.com port 25 Error performing GET. Curl ec:28 CURL Error Buffer content: Operation timed out after 8002 milliseconds with 0 out of 0 bytes received It looks like only AUTH LOGIN XOAUTH2 is supported and the lib is trying AUTH LOGIN. This was answered with silence for > 8 seconds and then timed out. Is there some flag or option we need to turn on in libcurl to allow SMTP sending through such email server? I already found the CURLOPT_XOAUTH2_BEARER option, but to be honest I don't know the process to get the values needed. From where do I get a Bearer Token? Do I have to ask the customer on every sending for some token? Or is this some setting the customer enters like a username and I have to save and use it? How does this work? Thanks! Volker -- Unsubscribe: https://lists.haxx.se/mailman/listinfo/curl-library Etiquette: https://curl.se/mail/etiquette.html