CURLE_UNSUPPORTED_PROTOCOL - ftp download fails - libcurl

Question

i use cURL (installed via vcpkg). Also openssl installed via vcpkg for a c++ project on VS 2019.
The problem:
CURLE_UNSUPPORTED_PROTOCOL = curl_easy_perform(curl);
I used this example:
https://curl.haxx.se/libcurl/c/ftpsget.html
with corrected connection and file data. The FTP server is filezilla. I checked the connection and file
download with filezilla client. All fine.
When i use the sample from link, i get the CURLE_UNSUPPORTED_PROTOCOL and in my FTP server i can't see
any connection try.
The error is described like this:
The URL you passed to libcurl used a protocol that this libcurl does not support..
Verbose information is:
* STATE: INIT => CONNECT handle 0x148090e0b38; line 1356 (connection #-5000)
* Protocol "ftp" not supported or disabled in libcurl
* Closing connection -1
* Expire cleared (transfer 0x148090e0b38)
I check the internet for the error message above and none of those i found solved my problem.
It seems not to be a format problem or problem related to wrong url .
So my question is, where can i enable this ? Do i need additional packages ? Or is the problem elsewhere ?
Many thanks

Answer 1

Mean while i figured out how to accomplish this using latest curl command line tool (version 7.68.0) on windows:
curl -u my_user:my_password --ftp-ssl ftp://my_ip/my_relative_path/my_file --insecure -o my_file
The file for download is on a server where a FileZilla FTP server is working. This server cyphers with a self created cert. The curl client only accepts this, when using flag:
--insecure
So far, i could not find the related options for my c++ curl. Perhaps it is not possible at all, because sources available through vcpkg are not (yet) up to date. But i want to stick with vcpkg. For me, this solutions: using command line tool instead, works fine.
One more hint, which is important: curl version 7.64.00 works NOT. You get error:
curl: (35) schannel: failed to receive handshake, SSL/TLS connection failed