FTP Settings

In store settings I have setup the ftp and used public_html/shop as the root as this is the directory OC is installed in..

However when I try to install an extension that is setup using ftp I get this error
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<b>Warning</b>: ftp_chdir() [<a href='function.ftp-chdir'>function.ftp-chdir</a>]: Can't change directory to public_html/shop/: No such file or directory in <b>/home/u846982487/public_html/shop/admin/controller/extension/installer.php</b> on line <b>299</b>{"error":"Could not set root directory as "}
====================

Can anyone advise on the problem.

Thanks

Solved it.

The instructions are incorrect.
There needs to be a "/" in front of the directory location - "public_html".

I am having the same problem.

However, my FTP Settings are set in the Settings panel.

FTP Host: 40f.225.myftpupload.com
FTP Port: 21
FTP Username: The same one I use when designing the website
FTP Password: The same one I use when designing the website
FTP Root: /
Enable FTP: Yes

The problem I am having is when I use the Extension Installer to Upload an Extension, I get the error: Could not connect as 40f.225.myftpupload.com:21.

Any ideas?