On Mon, 7 Apr 2008, Paul Andres wrote:

> I am attempting to transfer files to an ftps server the trace of my
> interaction is seen below:
>
> curl -v -k -3 -T "fei.xml" -u <removed>:<removed>
> ftps://<removed>/Cassini-candidates/

(you didn't state what curl version on what platform this is)

The use of ftps:// is the deprecated way to do ftp-ssl, and it may be an
indication that your server is adhering to an old ftps spec.

> == Info: Unknown SSL protocol error in connection to <removed>:990

I think this happens because the server doesn't expect the data connection to
be SSL-enabled while curl assumes that for ftps:// connections.

I believe this has been mentioned before, and the correct fix for this is
probably to make libcurl explicitly enable SSL for the data connection even
for ftps:// style transfers.

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