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Re: SMTP sending emails with curl greater than Version 7.40 with a batch file fails, Version 7.40 works

From: Dan Fandrich <>
Date: Fri, 24 May 2019 11:15:36 +0200

On Fri, May 24, 2019 at 10:58:34AM +0200, wrote:
> this ist the output of "curl -V" Version 7.40:
> curl 7.40.0 (i386-pc-win32) libcurl/7.40.0 OpenSSL/1.0.1j zlib/1.2.8
> libssh2/1.4.3

> This ist the output of "curl -V" Version 7.65:
> curl 7.65.0 (i386-pc-win32) libcurl/7.65.0 OpenSSL/1.1.1b (Schannel)
> zlib/1.2.11 brotli/1.0.7 WinIDN libssh2/1.8.2 nghttp2/1.38.0

The OpenSSL version is 4 years newer on this version, which is likely the
cause of the underlying problem. But whether it's an issue with OpenSSL or with
the remove server, I don't know. You could try downgrading to an older TLS
version at run-time with --tlsv1.2 or --tlsv1.1 (or even --tlsv1.0) and see if
that helps.

>>> Dan
Received on 2019-05-24